Gemini 4 pre training is underway: https://x.com/OfficialLoganK/status/2079594867161022817

My guess is we skip 3.5 and go straight to 4 Pro. With the monthly Flash releases, releasing 4.0 Flash and Pro in 6-8 weeks would be a nice buildup.

(I work at Google but don't know anything that isn't already public)