Confusion on Increasing Training Max or 1RM After Deload Week

I"m running the basic 5/3/1/ with my 17 year old son, and i have read two different things. One is to increase the training max 5/10 and the other says to increase the 1RM 5/10 after the deload week.

Just wondering which one to increase, he has made tremedous gains since starting in August

You increase the TM.

thank you