The snapshot can't find the mirror. It prints: "no address associated with this name". I have tried many mirrors (inclusing the mother, ftp.openbsd.org), none work for me.
I has been a hard time to work with snapshots since last month... many bugs. I'm using snapshots to help reporting bugs, of course, so I know that this kind of situation will happen some times. But, I can't crash the system everytime I do a new upgrade... I think it's time to just use stable.