Add the revenue/expense types to the Task&Alert designer. I have tried to create various combinations of the rule conditions, but the only one it picks up on is the VEXP - which then works on almost all the expense types. But there is no way to add a condition to the specific expense type. Have attached photos which hopefully will provide some clarity.
It would be good to have, so it was possible to make a validation rule, based on the expense type+sub code combination.