e.g. EGLL to KLAX, default cycle, default A346, cost index 500; parts of the flight are planned at M.88 (.876 in DLH/BER formats). Mmo for the A346 should be M.86
Looks like the segment planned at MACH .88 lies between T/C and the first step climb. I also imagine other aircraft profiles might also be affected but I haven’t tested them.