Has anyone else experienced issues as a Summit trying to take advantage of the new seats? I received an offer to upgrade to Stretch for free while checking in, but when I attempt to choose my seat, it says "There was a technical problem checking you in, please proceed to the airport". I spoke to the Summit line and they were not helpful, saying that my only option was to go to the airport and try for one, but I'm sure they'll be gone by then.

I went ahead and checked-in with my existing exit-row seat, but I was really hoping to try out the new configuration.