Update: I contacted the buyer and told them the only shipping option was through the GSP. He said he had no problem using the GSP and was willing to do that. I contacted Ebay again to find out how he can now pay for the item through the GSP. After explaining to them at least three times and speaking to a supervisor - they said there is no way to opt back in. Also - the real kicker and something I wasn't aware of is - the buyer didn't actually opt out of the program - he just requested an invoice from me and that opted him out of the program. Apparently, according to Ebay, if the buyer requests an item total that opts them out, and there is no way back in. Ebay said that there have been no complaints about this issue that they are aware of and that buyers and sellers often come to a mutual agreement to opt out for that order and that is the way to do it. They said I could cancel the order and relist it for the buyer to ship through the GSP. It's like the hidden menu at In-N-Out Burger...!
