What, MUSTs aims and priorities on the website? "Consult regularly with our match-going fanbase"? " Engage in regular constructive dialogue with senior club executives"? Can't recall seeing those on placards. And the things you do see on the placards generally aren't in MUSTs stated aims and priorities. So obviously, whatever this is, it's not a MUST operation, or MUST has some sort of strategy for this that isn't known.
Getting results through civic action doesn't just happen. If you want buy-in to things that have a negative cost, then people need to understand how and why that is necessary, and how and why that will bring which results. If they - whoever they are - are asking fans to support or participate in actions that will damage the club, then they need to show how there's a reasonable chance that doing that is going to lead to a result that will be worth the cost. At least in a general sense. If not, they're asking people to damage their club for no gain. If they want the authority to lead, then that's what they need to come up with. Just being angry doesn't cut it.
The fact that it certainly won't happen if you just stand around with placards is no sort of argument that it will happen if you do something different. That's just doing the "politicians syllogism" - 1. We must do something, 2. This is something, 3. Therefore we must do this.
So, a plan please. It doesn't have to 12 pages, just a handful of simple aims, principles and methods that plausibly speaks about how doing certain things will take us somewhere we want to go. Otherwise, this just looks like a bunch of angry people making a stink about something they want but aren't going to get. What they've got going for themselves is that a lot of us are angry about the same things. But again, that's not enough, and if they don't realise that, they're finished before they've begun.
The worst thing they could possibly do at this stage is to ram the cost and collateral damage of their approach down everyone's throats by getting another game cancelled, before they've come up with something credible to justify why they need to do stuff like this and just what it's going to achieve. They'll alienate a lot of the people they need behind them.