Applying for OPT on TPS with F1 status

[saroj35]

I am currently on TPS with EAD for Nepal but also have been maintaining my F1 status without any gap. I am doing my Masters and will be graduating this December 2018. In 2016, I went to Nepal and entered U.S. on TPS Advance Parole Document, since my F1 visa was already expired. So, my most recent I-94 has been stamped as TPS (class of admission: CH). My question is 
- When I apply for OPT in  December, will there be any problem because of my I-94 with my class of admission, even though I have my F1 status?
- If my I-94 has class of admission as CH, does that mean I need to change my status to F1 by re-entering to the U.S, in order to qualify for OPT? Or, are there other options?