Working singles into program

Intermediate lifter here. I am currently running a 5/3/1 program (building the monolith) and hoping to add in some singles into my plan. My question is, how many times per week would you recommend attempting singles? Once a week?

Based on what I’ve read, it is wise to work up to a 92% 1RM or RPE 8 single, and then use that number to base your est 1RM for your working sets.

Thanks!