The Mini 2 and 3, (not Pro), do not come equipped with obstacle avoidance sensors other than the two ground sensors. Recently a colleague was operating a Mini 2 in a rural area doing a fly by of an agricultural field. She reported that a low flying plane, likely a crop sprayer, approached the area. This apparently caused her Mini 2 to cease forward motion and hover in position until the aircraft left the area at which point the Mini 2 continued forward.   

This reportedly happened with another drone operator in a similar circumstance. Can anyone provide an explanation as to why this may have occurred.

There is a detection system for aircraft transponders, ADSB? or something like that, but I do not know if the Mini 2 has it. Nor do I know what response, if any, it imposes but, to me, "hover" makes no sense unless the system can actually calculate flight paths. To me, descend would make more sense, drones must always give way to manned aircraft, and down seems to be the safest thing unless of course the drone was above the plane.