Maybe it will be "My Old Memories".
You know, if it is tied into the current VN, it could be presented as a side story of shorter duration
(like Single Again is doing with three shorter VNs about the three main girls), allowing Killer to keep doing work on the "prequel", but not taking things too far off track from a time perspective - maybe keep it a AVSS (Adult Visual Short Story (copyright pending)) - and then be able to dive back into this full-force when he has his tech and assets back.
I can't remember the discussion of what the intent was around it (beyond keeping busy, keeping current, and giving his audience and supporters a good product while this VN has to be delayed), but I think most of his fans would like it.
ADDENDUM:
I didn't know this, or, at the very least, didn't remember it, as I wrote my post. I kind of like my idea, though (well, d'uh!), so, maaaaayyyyyyybe....