Is there a way to make the visibility of comments on Trello cards reflect the card's current board, rather than its initial board?

Question

This is the scenario:

• Roadmap board (set to private, members x & y)

• Project board (members x y & z).

• Card created on roadmap board, comment added by member x.

• Card moved to project board.
• Comment visible by member x & y, not visible by member z.

We ideally want to make comment visible by member z without making it an organisation board.

Answer 1

I have found a work around that might be a bit of a pain but does solve the problem. If the card that has been moved to the project board is copied by member x (select copy from the card menu, it defaults to keep all items), the comments will then be visible to members on the new board who were not members of the board it came from i.e. member z.