Yeah so there is no one solution fits all. I am just outlining the basic structure.
Every change has to be evaluated on a case by case basis.
Just weight paints alone, those would have to be transferred to a new mesh. It is a trivial problem. That does happen a lot.
But it depends. The rigger might just hand that file back to the modeler to continue with updates to the model, then work on something else in the meantime.
Changing a model with shapes of course would require handing that off to the modeler first.
No one is free to work independently without consulting the ramifications of what they are doing.
No production protocol can replace team coordination and communication.
And in general a working pipeline on a production is agreed beforehand. Or even some assets might get special treatment due to specific requirements.
But the general structure is as I have outlined. And then we take up the edge cases as they present themselves, but we do try and plan for the variety of problems beforehand.
We talk. We plan.
That’s the key.
But the main thing is to plan for things in a given sequence. Fixing problems always disrupts the flow one way or another.
So there is that.