What do I do if our K-1 is approved while my fiancee is temporarily visiting on a tourist visa?

[handsofholes 6]

My fiancee and I are awaiting our second notice of action (NOA2) for our K-1 Visa.

I am moving into a new apartment soon and when I sign the lease, she is going to come to the States on her tourist visa to help me move into it and make further plans for our wedding ceremony.

She will likely be here a month or longer and I am thinking that there is a chance that our K-1 visa will be approved during this time.

If it is approved while she is here, would she have to leave the States and return to her country to begin paperwork there immediately? Or would it be okay if she remained here and began it whenever we had originally planned for her to return?

And another question that is kind of related to this:

If the K-1 is approved BEFORE she comes here on the tourist visa to help me...

Will she not be able to enter on a tourist visa and help me out, return home, fill out the paperwork for the K-1 and do the interview and such, then return again to marry me?

[Harpa Timsah 13,258]

The NOA2 is just the petition approval, not the visa approval. She would still have to go home and do the medical and interview. She can continue her normal vacation though, no need to run home immediately.