Updating Sequence Diagrams after code import

[bp]

An EA numpty question, apologies if it's been covered before :

I have imported a load of code into EA and produced a variety of diagrams from the project browser by dragging objects into the diagram area and creating as simple links.
The code was updated externally so I re-imported into EA, no probs.
Except, the sequence diagrams are still displaying some methods with the same signatures as before, even tho signatures have changed in the update.
You can create a new message on the diagram with the updated method, and you'll have the same message on the diagram but with 2 differing signatures.

Any idea on how I sync the diagrams with the new code ?  Obviously it would also be preferable if I didn't have to visit every single diagram manually to check all message signatures on the off-chance they have changed in the code update.

Thanks in advance ......
B