Yes, the limit to the production rate and the mutation rate is for 1.5.2 and higher. The maximum production rate is down from a factor of 64 (with 6 frames) to a factor of 16 (with 4 frames). The mutation rate is down from guaranteed mutation to a factor of 10. Anything beyond that and you risk your princess to turn into a Swarmer bee.
But at the same time you can now also use Creosote Oil instead of Seed Oil for making Alvearies, which makes it easier to just increase the number of Alvearies. (It now makes also sense to breed all the way up to Fastest speed, which is a 40% increase to just "Fast", which you get already from Cultivated Bees.)
And I think it was mentioned before, you can still go beyond these limits. Then cross the fingers and hope you get enough drones from the princess to extract the traits you want, before the bee disappears.
Meh, this is downright silly IMHO. Just unnecessarily increasing calculations in the server world tick for no reason by forcing the increased number of alvearies.