Presuming previous auto renews were done in a similar way (no clue on this but I can see why a 3 day earlier window is put on.) Also flip it, as its on auto renew whats stopping them doing it on Day 1 of the window opening, as far as the software for this is concerned, approval to renew has been given . So have they built in a longer window to allow people, who have remembered of course, a chance to back out
As for the shady bit, probably but thats what an auto renew does. Put on here yesterday, I was done for a subscription on Premier Sports last year after failing to remember I had even take it out. I got an email from them to tell me the subscription was sorted and they had done the renewing 3 days before sending that. Thats shady and they refused to cancel and refund.
The only thing I would aim at the club in this instance is not sending out a reminder when the details were released to say if you paid by DD last time and kept the auto-renew option, the ticket will be renewed on the 27th July. No clue if they have done that before, so standard behaviour from them (and matching all the other companies that use auto renews options)