It seems now that SS just hold all your batches in pending and review them all at once, which means you can't stagger uploads to release gradually across the week any more. 

Given the changes in review times (five days on my last batch), I'm now getting situations where (for example) a batch uploaded on a Tuesday + a batch uploaded the following Friday are both reviewed at the same time and released to the market on a Saturday.   Once I thought I understood what was going on, I surprisingly had a review within a day and a half of upload, which didn't work well for me either. 

I don't know if others are experiencing the same.

That's very interesting.  I have noticed better reviews at the weekend too.  I'm glad to hear you're still getting fast reviews at least.  Maybe they just don't love me any more

Thats how they used to do it, you'd upload one just to mark your spot and then prepare the rest and they would all be reviewed at the same time.