Hi James, there is a new "RemoveAndFill" function in v5 that can be used for this case.
You can access it by selecting the face:
Then use Shift+Delete:
It's also possible to do an "untrim" to erase a trim boundary to uncover the underlying surface. That's done by separating out a surface so it's not joined and then select all edges of a boundary and use Delete.
Some info on untrim here, but Shift+Delete is more convenient:
