This is the first time I’ve noticed this feature (X2D, Bambu Studio 2.8.2.61). Was this added recently, or have I just somehow missed it until now?
It’s a new refinement, yes.
This is a description of how it works. Basically, always center your parts on the bed, if it falls within one of the inner zones the printer will need less time to heat up and stabilize before it probes the bed.