Build times

Does anyone else see that build times are no longer accurate? I had a Durable Resign print the other day and it noted less than 18hrs. Ended up as 21hrs 12min. My Rigid print today, not complete yet, stated 8hrs. Time keeps extending. Should have been completed by 3:30 and now shows a completion after 4. Assume will be even later than that. In the past, all printing was less than the time stated…never more. Thanks