sure,
As long as you or your lawyer can convice INS that you are going to join your sponsorer by end of the green card process you should be fine.
the one way to convice INS to continue job with employee or maintaining other legal status F1/ H1/ L1 (if it is for future employment)
I don't think full time student doesn't have to be f1 visa holder.
And you are risking contradicting yourself by applying f1 (becuase f1 is not duel intent visa, it's only for study not for immigrant purpose, so i would even try to think about f1 visa while I-485 is pending)