Observed by playing engine games on Infinity on a 32 core AMD 2990wx with the numa version from
August 21 from http://chess.massimilianogoi.com/download/cfish/
Setting was
Move Overhead = 250
Slow Move = 50
It was a 12 min (+2sec per move) game, but I observed similar behavior in other games. Seems less critical in blitz games. Cfish announced mate in 10, had 50 sec left and used about 6-10 sec for each of the following moves loosing for time.