The two week gap could be because of additional checks or because UEFA just want the delay for some reason. Every club is in the injury boat beforehand though and even if announced today, it wouldn't make any difference as someone could pick up a season ender between now and the first match in the competition.
As pointed out, only really one "first teamer" is in doubt of missing out. Maybe one of the kids we bought in the last two year who hasn't been loaned out would have gotten a chance if we had two of those, but I couldn't name one off the top of my head.
