rift mystery eggs

my dragons from mystery eggs used to come without the rift trait, but i just recently bought one of the chrysalis and monolith eggs and both had it. but at the same time, those are both limited time eggs and when i used to get non-rift dragons they came from eggs that are available year-round.

did they change this or are limited eggs different from eggs that are always available? (sorry if this is extremely confusing, i couldnt come up with a better way to word it)