This would allow the user to select and make activities N/A in bulk fashion, just like the call up/call off/start/complete/approve functionality.
This would still consider the following:
The activity cannot be made N/A where there is an order linked.
The activity cannot be made N/A where there is an unlinked order for the cost centre.
This could be beneficial where there are many of the same type of activities that might be in a standard programme, that do not apply to many jobs. This would allow you to select and Make N/A all eligible activities.