As far as I can see the club haven’t asked you to give a reason for non attendance, just to let them know if you can’t attend.1 - reasonable
2 - Unreasonable... (although its not as black and white as that either...) - If i know 1/2 weeks beforehand then its reasonable to expect me to contact them.. even if they can't re-sell my ticket.. I shouldn't face sanctions or even be threatened with sanctions for non attendance. IMO Its not up to the club to act as judge and jury on confirming if my reason for non attendance is acceptable or not..... that's the whole point......
I also agree the club should not issue refunds... Don't have a problem at all with no refunds being provided for non attendance as a result of circumstance change... That's on you not the club...
It is entirely up to the club who they sell tickets to and if they decide not to sell tickets for particular game to someone who didn’t follow their instructions so be it.