We have taken a move over offers once, it wasn't a full refund per se, but it was a full amount as refundable OBC on the free cruise that we picked, similar length. Our offer was done a week prior.
Yes, Greece can make you slip up and Con is a Greek name, goes well with concrete, they are hard, and here in Australia especially in Sydney, they were notorious for removing their front lawns and concreting them for small gardens and car parking. The back yards were more like market gardens,
It was one of the options, there were others. The morning of was bad form, but a few days prior would be fine for most people.
Squeaky wheels always get more grease.