Thanks! They'll move to tech 3 in the next release.
One is supposed to write migrations when a tech gains recipe unlocks, because when you already have it researched, it doesn't add them automatically in a running game, but I hope I'll get away with not doing it, as stacking 3 requires tech 2 to be unlocked already, so it shouldn't be possible to not either already have the recipes unlocked or get them when researching 3. Heh, that sentence is confusing, I'll blame sunday ^^.