Sorry the image was incorrect.
Anyway. The original query was looking for 2 cirteria.
A: The engineer covers the area of the job
B: The engineer is not "unavailable" according to booked holidays on the holiday table.
What i need, is a query that will return all engineers that cover the area. Then instead of REMOVING the engineers that are on holiday, simply highlighting them as unavailable.
I had an if statement in the report on load, that checked this. However it highlighted all engineers based on the status of the first one returned.