The following is still rough and is primarily my notes for a potential book, hence the other details and TV ratings. Some stuff is speculative. I have/had sources for everything but may not be able to track them down again, but everything here is from a source.
July 1993 – Uru in Blue is shelved.
July-September 1993 – Anno drinks with Toshimichi Otsuki, King Records representative, who decides to collaborate with Anno on a project, “anything.” Meetings regarding Alcion, battle between gods and humans, Devilman, Gunbuster, A10 nerve, dead mother in robot, Ideon. TV, movie, or OVA.
20 September 1993 – Anno submits a first draft proposal of Evangelion.
5 January 1994 – A second draft series plan featuring synopses of all 26 episodes submitted.
4 February 1994 – Internal draft fixed.
April 1994 – Planning Draft for external distribution completed.
14 May 1994 – Sadamoto Angel concept art.
29 November 1994 – Most final designs approved.
8 December 1994 – Proto Eva-00 designed.
19 December 1994 – Eva-00 face design finalised. #05.
26 December 1994 – Manga adaptation of Evangelion begins in Monthly Shonen Ace by Sadamoto using existing materials, scripts, and storyboards. Chapter 1 covers first third of episode #01. Evangelion final colours and cockpit design not finalised.
28-29 December 1994 – Character designs for episode #05 finalised.
January 1995 – Work on the first few episodes in active production.
January 1995 – Manga chapter 2 covers middle third of episode #01.
22 January 1995 – Rei’s room finalised.
25 January 1995 – Episode #05-#06’s (5th A) Ramiel design finalised.
February 1995 – Manga chapter 3 covers last third of episode #01.
March 1995 – Manga chapter 4 covers first quarter of episode #02.
Spring 1995 – Speculative original premiere aborted to the fall.
Spring 1995 – Oikawa Neko writes A Cruel Angel’s Thesis in 2 hours to the incomplete #01/#02.
25 March 1995 – The future VA’s for Misato and Rei confirm that they’ll start recording for a new mecha called Evangelion in a radio show.
April 1995 – Production for Episode #01 completed.
April 1995 – Manga chapter 5 covers final quarter of episode #02.
16 April 1995 – Kaji episode #08 appearance finalised.
28 April 1995 – Eva-02 face design finalised. #8 angel designed. #11 angel designed.
May 1995 – Production for Episode #02 completed.
May 1995 – Manga chapter 6 covers second quarter of episode #02.
1 May 1995 – Episode #11 Angel design finalised. Prog knife release mechanisms for Eva-01 (#03) and Eva-02 (#08) finalised. Eva-01 spear for #09.
2 May 1995 – Episode #09 Misato design.
7 May 1995 – Episode #03 (4th A) angel designed.
11 May 1995 – Shinji episode #09 designs.
12 May 1995 – Asuka’s episode #09 design finalised.
18 May 1995 - #11 onward design of Eva-00.
June 1995 – Manga chapter 7 covers third quarter of episode #02 and half of episode #03.
16-23 June 1995 – Misato’s episode #07 designs.
3 July 1995 – Eva-02 and 00 cockpit designs finalised. Magma diver suit finalised. Sandalphon finalised. #10.
July 1995 – Manga chapter 8 covers an extended original sequence set within episode #03.
17 July 1995 – In a letter for later publication, “What are we trying to make here?” Hideaki Anno states that he doesn’t know what will happen to Shinji, Misato, or Rei.
22-23 July 1995 – Gainamatsuri Gainax Festival at Itako, Ibaraki, screens the first two episodes. OP and ED sequences neither animated nor storyboarded yet.
August 1995 – Manga chapter 9 covers third quarter of episode #03.
September 1995 – OP and ED sequences finished.
September 1995 – Manga chapter 10 covers the climax of episode #03.
27 September 1995 – Teenage Mutant Ninja Turtles airs its final episode and promotes Evangelion with shots from episodes 1, 5, and 8.
October 1995 – Manga chapter 11 covers end of episode #03 and an extended half of episode #04. Up to episode 8 is completed, and only half were in the drawing stage.
4 October 1995 – Airing of Episode #01: Shito Attack/Angel Attack. 6.8%
11 October 1995 – Airing of Episode #02: Unfamiliar Ceiling/The Beast. 5.3%
17 October 1995 – Episode #19 (14th A) angel designed.
18 October 1995 – Airing of Episode #03: The Phone That Won’t Ring/A Transfer. 7.1%
25 October 1995 – Airing of Episode #04: Rain, After Running Away/Hedgehog’s Dilemma. 5.8%
November 1995 – Manga chapter 12 covers second half of episode #04.
1 November 1995 – Airing of Episode #05: Rei, Beyond the Heart/Rei I. 7.2%
8 November 1995 – Airing of Episode #06: Decisive Battle in New Tokyo-3/Rei II. 7.7%
15 November 1995 – Airing of Episode #07: Human Creation/A Human Work. 5.9%
22 November 1995 – Airing of Episode #08: Asuka Arrives in Japan/Asuka Strikes. 7.6%
29 November 1995 – Airing of Episode #09: Moment, Heart, Together/Both of You, Dance Like You Want to Win! 7.1%
December 1995 – Manga chapter 13 covers first third of episode #05 and is outpaced by the anime.
6 December 1995 – Airing of Episode #10: Magma Diver/Magma Diver. 9.5%
13 December 1995 – Airing of Episode #11: In the Still Darkness/The Day Tokyo-3 Stood Still. 9.0%
20 December 1995 – Airing of Episode #12: The Value of a Miracle/”She said, ‘Don’t make others suffer for your personal hatred.’” 7.4%
21 December 1995 – VHS release of Genesis 0:0 In The Beginning, a promotional video for the series.
27 December 1995 – Airing of Episode #13: Shito Invasion/Lilliputian Hitcher. 3.4%
End of December 1995 – Anno finally decides on an ending, putting aside the written #25.
3 January 1996 – Airing of Episode #14: SEELE, Seat of the Soul/Weaving a Story. 0.9%
10 January 1996 – Airing of Episode #15: Lies and Silence/Those women longed for the touch of other’s lips, and thus invited their kisses. 6.0%
17 January 1996 – Airing of Episode #16: Sickness unto Death, and…/Splitting of the Breast (16mm film lost, post-Renewal releases use 35mm). 9.1%
24 January 1996 – Airing of Episode #17: The Fourth Qualified Person/Fourth Children. 7.3%
31 January 1996 – Airing of Episode #18: Choosing a Life/Ambivalence. 9.6%
3 February 1996 – VHS/Laserdisc release of Genesis 0:1, episodes 01-02.
7 February 1996 – Airing of Episode #19: A Man’s Fight/Introjection. 8.0%
14 February 1996 – Airing of Episode #20: Shape of the Heart, Shape of the Person/Weaving a Story 2: oral stage. 7.4%
21 February 1996 – Airing of Episode #21: The Birth of NERV/He was aware that he was still a child. 7.7%
28 February 1996 – Airing of Episode #22: At Least, Be Human/Don’t Be. 7.9%
4 March 1996 – After recording #25, the voice actors invite the animation team (working on #26) to a party.
6 March 1996 – VHS/Laserdisc release of Genesis 0:2, episodes 03-04.
6 March 1996 – Airing of Episode #23: Tears/Rei III. 6.9%
13 March 1996 – Airing of Episode #24: The Final Messenger/The Beginning and the End, or “Knockin’ on Heaven’s Door”. 6.0%
20 March 1996 – Airing of Episode #25: End of the World/Do you love me? Ironically, also the one year anniversary of Aum’s sarin gas attack. 7.7%
27 March 1996 – Airing of Episode #26: The Beat that Shouted Ai at the Heart of the World/Take Care of Yourself. 10.3% Over 1/10th / 10 million of the country was watching.
5 April 1996 – VHS/Laserdisc release of Genesis 0:3, episodes 05-06.
26 April 1996 – Gainax/Anno announce that episodes 25 and 26 would be remade for the home release as a form of OVA, followed by an announcement of a completely new, original, unrelated, standalone Evangelion film in summer 1997.
2 May 1996 – VHS/Laserdisc release of Genesis 0:4, episodes 07-08.
5 June 1996 – VHS/Laserdisc release of Genesis 0:5, episodes 09-10.
July – Decision?
5 July 1996 – VHS/Laserdisc release of Genesis 0:6, episodes 11-12.
7 August 1996 – VHS/Laserdisc release of Genesis 0:7, episodes 13-14.
5 September 1996 – VHS/Laserdisc release of Genesis 0:8, episodes 15-16.
1 October 1996 – The Gainax website announces that the Evangelion movies will be a double feature omnibus of the TV series paired with the remade 25/26 to release in spring 1997, and that in addition there will be a completely new original movie to follow.
2 October 1996 – VHS/Laserdisc release of Genesis 0:9, episodes 17-18.
25 October 1996 – Titles of Evangelion Death and Rebirth announced.
1 November 1996 – Death and Rebirth press conference and first Death and Rebirth trailer.
23 November 1996 – Advance ticket sales begin, setting a new record at over 200,000.
5 December 1996 – VHS/Laserdisc release of Genesis 0:10, episodes 19-20.
9 December 1996 – Materials intended for Rebirth/25 are in production.
12 December 1996 – Release of After the End comedy drama CD.
21 December 1996 – An ad campaign encourages viewers to buy a poster on this date for Evangelion: Death and Rebirth.
9 January 1996 – Materials intended for Rebirth/25 are in production.
19-25 January 1997 – Shooting of abandoned live action sequences.
25 January 1997 – VHS release of Genesis 0:0’The Light From The Darkness, a Death and Rebirth preview.
February 1997 – A trailer for Death and Rebirth includes incomplete shots from episode 25’, and audio from 26’ that doesn’t appear Rebirth. The trailer has no release date.
2 February 1997 – 2:55am rebroadcast of episodes 1-4. 5-6%
9 February 1997 – 2:55am rebroadcast of episodes 5-8. 5-6%
9 February 1997 – 14 hour movie dubbing session from 10am to midnight.
14 February 1997 – Precisely a month before the premiere, an emergency press conference is held announcing that Rebirth will be incomplete. Anno apologises. A tentatively titled Rebirth 2 (while posters bearing the name The End of Evangelion are present) will be released in the summer. Unused tickets for Death and Rebirth will be valid for the summer film. The completed summer/Rebirth2 release is estimated to be 70 minutes long, 16 mins short of actual.
16 February 1997 – 2:55am rebroadcast of episodes 9-12. 5-6%
23 February 1997 – 2:55am rebroadcast of episodes 13-16. 5-6%
2 March 1997 – 2:55am rebroadcast of episodes 17-20. 5-6%
7 March 1997 – Evangelion: Death screening with series marathon.
9 March 1997 – 2:55am rebroadcast of episodes 21-23. 5-6%
14 March 1997 – Neon Genesis Evangelion: Death and Rebirth screening – live action shooting.
16 March 1997 – 2:55am rebroadcast of episodes 24-26. 5-6%
25 March 1997 – Theatrical release of Neon Genesis Evangelion: Death and Rebirth
24 April 1997 – Some late materials intended for EoE/26 are in production.
May 1997 – Announcement that Rebirth 2 is retitled to The End of Evangelion and given a release date of 19 July. Plans for the original Evangelion film are abandoned.
1 May 1997 – Some late materials intended for EoE/26 are in production.
8-10 May 1997 – Shooting of final live action sequences.
19 July 1997 – Theatrical release of The End of Evangelion
19 July 1997 – DVD release of episodes 1-4.
21 August 1997 – DVD release of episodes 5-8.
26 September 1997 – DVD release of episodes 9-12.
22 October 1997 – DVD release of episodes 13-16.
22 December 1997 – DVD release of episodes 17-20.
2 January 1998 – Airing of Evangelion: Death True on TV with NPC cuts removed.
4 February 1998 – VHS/Laserdisc release of Genesis 0:11, NPC episodes 21’-22’ only.
8 March 1998 – Theatrical release of Revival of Evangelion (Death True 2 (OG Death minus #23 Asuka scenes) and The End of Evangelion)
3 July 1998 – VHS/Laserdisc release of Genesis 0:12, NPC episodes 23’-24’ only.
12 August 1998 – VHS/Laserdisc release of Genesis 0:13, episode 25 and a unique version of 25’.
9 September 1998 – VHS/Laserdisc release of Genesis 0:14, episode 26 and a unique version of 26’.
27 November 1998 – DVD release of NPC episodes 21’-24’ only.
1999 – Laserdisc release of Genesis 0:X containing the broadcast versions of episodes 21-24. Limited run bonus disc for purchasing all 14 laserdisc releases.
22 January 1999 – DVD release of episodes 25-26 and the Genesis versions of 25’-26’.
22 September 1999 – DVD release of Death + Rebirth and The End of Evangelion.
2000-2001 – Limited edition DVD boxets containing the broadcast versions (only) of 1-26 and Death + Rebirth and The End of Evangelion. Limited to 5000.
2003 – Renewal DVD releases of all the broadcast versions of 1-26, all the NPC versions of 21’-24’, Death, and The End of Evangelion.
26 August 2015 – Release of Blu-Ray box, combined with Archives of Evangelion DVDs, everything has finally been released.
Additionally, my theoretical schedule. I don't know when most things were written, but the pink represents time I know something was written, yellow represents production time, blue represents a specific swapping of scenes between #15 and #24 and isn't accurate but it's information I need, orange represents airdates/releases. The final four columns acknowledge the changes in the ending OVA/movie projects as time progressed and they each split and stopped. Everything is vague but somewhat backed up by production art in the timeline above, anecdotal evidence, and a matter of logistics by not allowing episodes worked on by the same people overlap in the schedule.
It might surprise people to see the actual amount of time spent on episodes, even the speedier ones. But it's very clear that they spent far too much time on the early episodes, and as production continued it started colliding with the airdates.
I can answer questions on either of these since they're very unclear and unpresentable and in-progress. Due to their unpresentable nature,
I would ask for none of it to be put onto the Wiki or allowed to spread beyond this forum.