Is it set when the job is scheduled, or is it set when the job actually starts running? I tried reading The Docs, but didn't see anything about it.
There's a few times I have a bunch of systems that might affect a chunk based on what's calculated in the job or in a previous job, but since scheduling it causes it to "set" the write flag either way, I usually have to figure out at Schedule-Time if the job will do something or not and just not schedule it.
But if the change version is set at Job-Time then it'd be nice to write an IJobChunk that I can choose if sets the write flag or not.
If it's at Schedule-Time then that might be useful for some checks in other systems, but iirc most functions on queries that can be used on the main thread blocks until scheduled jobs are over anyways, so I'm not sure if that helps anyways?