@Dean_Brown the advanced checklists feature is available for boards that are part of a business class team. Probably the issue is that your board is currently a personal board, and you'll need to change it to be a member of the team you upgraded to Business class.
@Dean_Brown there are no options to receive notifications via TXT except by integration with something like Zapier or IFTTT. You can receive notifications via email, however just be aware that even if you have your notifications set to "instant" they will actually only be sent after about 5 minutes and only then if you haven't read them anywhere else (ie. web/mobile app) and they are also grouped:
Note that you also won't be notified about actions you take or that other apps take using your API key (for example Butler commands that you install can't notify you except by using the "send email" action on a paid account).
Ultimately I found that the best way to receive Trello notifications is by the mobile app or using desktop notifications, the only problem is that if you're added to a card you watch them by default, so I created this integration that automatically unwatches any card you're added to so that you only get notified about being added to a card, mentioned in a comment and removed from a card:
If you had to thrive a new habit during a lockdown, what would it be? Trello
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