ATC_STR_ACC_MAX and PIVOT_TURN_RATE

During a pivot turn, should Ardurover increase rotation from 0 deg/sec to PIVOT_TURN_RATE deg/sec at ATC_STR_ACC_MAX deg/sec/sec? Should it accelerate at any other rate? Or does it immediately command PIVOT_TURN_RATE? (This is what I’m observing).

Thank you!
FYI @tridge