Tested keeping the same thumbnail style for 30 to 60 days

Has anyone tested keeping the same thumbnail style for 30 to 60 days on one channel?
Did YouTube seem to understand the audience faster or was there no real difference?

sort-of? consistency helps, it trains viewers to recognize your content faster which can improve CTR over time, but it only works if the style actually attracts clicks

I think new content is key to attracting viewers on YouTube. Besides that, you can revolve around a theme using different methods of presentation, rather than consistently following a rigid, formulaic approach that creates boredom. Give a car to the viewer.

It definitely helps the algo find your cluster faster. When you keep the style consistent, the system doesn't have to guess who your audience is every time you upload.
If you're constantly switching styles, you're basically resetting the testing phase. Stick to one look for at least 30 days - it helps the AI categorize your channel much quicker.