I was just thinking the same. What difference does it make that they stay a little longer tonight and make sure the deal is concrete and finished, or leave it unfinished over the weekend whereby clubs might think "he's had second thoughts, we could swoop in here" and leave him to go somewhere else? No other club has matched the asking price yet, but it doesn't mean they won't if they've got two days in which to do it. Usually at this point the agent pipes up and says "oh it's a done deal, he'll be signing Monday", so if there's radio silence, it's a tiny bit of a worry.
Like I said in the other comment. If you had worked at a place that does press releases you would know that it is standard procedure to try and never do announcements on Fridays or the weekend. Its not a worry at all, in fact it would be a bigger worry if our club did announcements on days that you are not supposed to do them. The club is run poorly enough from a marketing point of view without ignoring basic rules like that.