Found this, probably very unreliable, ring them before travel.

Yes, Blackburn Rovers typically allow away fans to pay on the day at the Darwen End away ticket office, with cash and card payments accepted and no price increase compared to advance sales. Fans should arrive at least 45 minutes before kick-off to avoid queues, as turnstiles open 90 minutes prior to the match. 

Posted By: Goosebumps, Aug 29, 23:50:30