Hello @Theon
The update for FP6 with February SPL has just been posted
If you want to get the gist on how FP has been doing with updates so far, you may find this webpage useful, as it lists all the past updates.
FP6 is expected to be supported for three years with montly updates, and afterwards with bi-monthly ones. I believe that was the information available from the start.
https://support.fairphone.com/hc/en-us/articles/9979180437393-Fairphone-s-Operating-System
After checking all of that, I guess you would need to make a decision whether that is safe enough for you.