You can relist either way.
Thru the summary sheet in ebay, or thru Auctiva. I like relisting thru Auctiva because I can schedule it. I don't go to the closed listings tho, I don't believe that way of doing it has the scheduling feature yet. I just re-schedule the original saved auction.
Luckily I don't do it too often or I'd be losig a ton of fee credits