Timeline

it depends on several factors, but for an auto the range is 85-105. The flush is useful ONLY for saving the fertilizer money fot the last week ;)

i don't see any reason to flush your substrate. It does not look to have a toxicity of any kind? If you think something is running a bit high, reduce concentrationa bit. If you want to be lazy, you can give water only the last 3-7 days or so in soilless context. It won't have any negative impact that would matter. "where you shoudl go with it" should not be based on an arbitrary feeding schedule but based upon observancae of the plant. Do they flush outdoor plants? No, because that's absurd, lol. Do it to be lazy and don't want to mix the fertilizer, but don't do it because everyone else is doing it. It's bro-science. You've got a very long time, yet. Those are just-formed buds. Might be anotehr week or 2 of noticeable plumping, then another week or two of ripening. All you have right now is long white hairs (stigmata). It's fairly early in the process. 4-5 more weeks is a good guess... genetics vary. maybe you have a fast developer or a slower one.