If we get B5 on 3 August and weekly thereafter, that will mean there are 9 betas before public release around Sep 10.
This does not seem likely with such stable betas.
Hence I think we get B5 on 10 August, resulting in 8 betas before public release around Sep 10.
I think we’ll get 9 betas but public release will not be until likely 9/23 assuming they hold the iPhone event the week after Labor Day here in the US. Could be later if there are phone shortages due to chip issues.