Say I booked a flight on United that departs July 1st. Return ticket is for October. Between flight to destination, and ticket departure date, I fly back home using miles.

If the ticket is class V and fully refundable, what are my options for the credit of flight back?

A) one way back to that destination then take flight home.
B) Change ticket and pay $300 fee but have to get back there.
C) Change ticket to a completely different coming/going and use the credit from that ticket towards new one.

Anyone?