While there are (seemingly) current issues with covid/supply chains along with the notion that shipping laptop chips is a 'new-ish thing' for Apple, I'd bet they'll want to get to a yearly cadence, just as with the A chips.
One thing that supports that idea: Here's the average historical release cadence for 13" Mac Book Pro:
346 days
Per
https://buyersguide.macrumors.com/#MacBook_Pro_13
I'm thinking this decade will be ushering in technological advances at a faster pace, so there's no reason to think Apple won't be part of that. There's no reason why Apple wouldn't design some of these updates as SOC-only updates. Historically, not every rev gets a new design.
I also think this because for every TSMC node that Apple doesn't bogart, it'll leave more TSMC capacity for Intel to lap up. If you think about it, there's probably pretty good economic sense for Apple to lower prices on future chips to increase demand and put the squeeze on Intel from both a pricing and 'blocking TSMC manufacturing capacity'. I'd like to see what that analysis spreadsheet looks like.