I'll try and clarify this.
We do not charge for issuing a MAC (but as the OP has confirmed, they have not requested this).
What has happened is that Talk Talk have put an order to cease the PSTN line, which the broadband is tied against. As they have actioned this as a cease and re-provide, we are charged for the cessation of the broadband in line with standard Openreach fees.
Talk Talk need to book this as a Cease (M) which is a migration (and cease), which they've not done. This type of cease (even without a MAC) is not chargeable.
Billing are likely to confirm this to you on Monday but they're not in on the weekend.
Talk Talk are the only ones that can change the order to ensure that you're not charged such a fee. We have no control over the order type they place to take over the service., nor can we modify or even cancel it - only they can.
Until the existing order is cancelled (from Talk Talk's end), we cannot issue a MAC. You either cease outright or have MAC - you can't do both. Even if one was issued, Talk Talk won't use it as they're an MPF operator (who don't use MACs)
No, we can use Talk Talk's equipment too! Contact us and we can give you details about those products, move you over to it for free and stop you getting billed a cessation charge (as we'll do the order correctly!

)
Matt