That wasn’t my experience. I agree that you cannot reinitialise. Unfortunately I don’t seem to have saved the sketch in which I experimented. I think you may need to take 2 or 3 pics after coming out of standby to re-establish the white balance but the camera did work. You do need to reinitialise the camera after a deep sleep.
I will be returning to this topic later this month when i have got my Image library working.