There are some very simple ways around this. For example don't enter into an agreement with a prospective buyer that doesn't allow you to do something fundamental like design and release a kit or speak to the new buyer and agree that you'll go ahead with the kit and they can change the deal the following year, or continue with the current supplier and allow the prospective buyer to change next season. Alternatively, don't enter into agreements with people who aren't really serious about buying the club.
We lost the play-off semi final around 2 months ago, someone at the club has said that the sale was dependent on us going up. We therefore knew it wasn't going to happen 2 months ago as soon as Gibbs-White missed that penalty. Crack on at that point.
No, just the Blades. As I said above, we aren't using the 'supply chain issues' as a reason. If other clubs are then that's on them and their fans can question them. We are using this club purchase as an excuse. The reasons that this shouldn't have been an issue I have written above in response to another post.
If you're happy with "it is what it is" then fair enough.
I don't think it's good commercial practice for the club to be in this situation, particularly when Bettis came out and said it was a great commercial deal for the club. I assume that this probably relied on shirts being available to sell to fans. I'd hope that the club have contractual penalties with Errea to cover the shortfalls if and when they occur.