Marrow rr with btr

I am a post intern i have done marrow rr from beginning but have not been able to clear neetpg25….so this time i have decided to do marrow rr+btr+btr tnds along with pyqs and gts

but i want marrow rr to remain my main source coz i have read it multiple times…..still i also want to do btr this time….so i am confused about what i should do and i am also bad at integrating subjects and concising them

1. Should i do marrow rr first then watch btr and mark the topics not present in rr …and do only those extra topics from btr in my nxt revision along with rr or

2. Do both subjects together till the last month of exam then shifts only to marrow rr