I don't think the mortar itself has been changed, but the riflemans resistance too it has (no resistance now). Also i find that the mortar is a lot harder to dodge now because of that prediction bug, sometimes I see the shell go way short and think "oh good I've got time" then get blown to bits.
Splash was changed during our internal testing to 350 inches then back to 210. Resist to mortar fire for rifleman is set to 0 now. Damage might have been buffed but only a bit.