Hi @Phil Brunton if you enable more than one Power-Up on your board, using Trello Gold or Business Class, free users on that board will still be able to view and use those Power-Ups. However, they won't be able to turn on any additional Power-Ups on that board, as free users are limited to one Power-Up per board.
Here is a link that features this answer as well as a few more details that you may find useful:
Please let me know if this was helpful.
Have a great day!
If you had to thrive a new habit during a lockdown, what would it be? Trello
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