1) I've done the "delete images" before their time on my FTP site and it didn't seem to upset aw2k. I can't say for sure about the date stamp however.
2) When you are going through the process of uploading new auctions. Aw2k comes to the part where it uploads your photos - it first goes through the deleletion process of those photos who's time has come.
Hope this helps
rodgw