Can F1 move to F2B if petitioner was USC before filing.

[Seun Ajayi]

I am the beneficiary and currently F1 is crawling, F2B seem to be doing well.
My petitioner became a USC before filing because she was misinformed that she can not file until she is a USC

I am currently on the F1 category and was looking at the sexy F2B hoping i could opt into it

Note:i was never in F2B.
is the opt even possible given that at one point the petitioner was a LPR,

if a USC is also a LPR, that may be possible.