There is no limit to the number of times you can actually do EOCS and Blue boxes (now black boxes, sigh!)… I used to do them couple of times and realized actually I was repeating the mistakes I did the first time around. So definitely helps doing it couple of times.
Schweser (or finquiz) is helpful too though imho. There have been mixed views on this, so do the stuff which worked for you in L1/L2.