Base assault bases don’t spawn even if region threat level is max.
I have tried this on new saves but the problem is still present
I have been able to only try this in the farmland region because of irl time constraints
Rivals spawn normally
This happen on ps5
I don’t know if it’s a prerequesite currently, but did you finish building blocks mission?
Yes I did and they wouldn’t spawn but I have noticed that sometimes the control points don’t show up on the map even if discovered in new saves after I complete the building blocks mission
hhmmm
is it the cooldown time?
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Hello there @Lazur327 
Repeatable Home Base Defense Missions (the mission where waves of machines attack the home base) can be unlocked by winning battles in the region, similar to how rivals are created. Your region score influences your chance to unlock missions. After unlocking, the same mission can not be unlocked again for an hour.
Home Base Defense missions can be restarted and replayed as many times as you wish, after you have completed or failed them. To unlock them subsequent times after completing them once, you need to increase the corresponding Region’s insurrection level, just like when you are trying to provoke a machine into evolving into a Rival: by destroying enough machines in that Region.
EDIT: The second paragraph/explanation (above) is also available in-game as a tutorial that is triggered after completing the horde mission for the first time. The text can also be read in the tutorial section of the log menu at anytime.
I hope this makes it clearer how the Home Base Defense Mission works, and IF not, please let me know and I’ll try to explain it better!
Sorry for the confusion and thanks for reporting! 
Do you already have some FNIX bases in a region? I believe there’s a limit on the number of active bases in a region.
I never do them, and as such haven’t had any spawn for the longest time.
I don’t have the region base limit maxed because I used to do base assaults and then raise the threat level to spawn more but now no bases spawn regardless of a high or max threat level