I’ve been able to duplicate this bug on all occasions except when you have a contract to destroy the location.
Pause and Save just outside an enemy location,
After the battle, don’t unpause,
Here, you can manage equipment and save then,
You should be able to mouse over the location and the sword icon should appear,
If you click on it again then you can fight at the same location against the same enemy type.
I’ve been able to quickly farm gear and levels with this trick.
-Riecheck, Lion of the Alliance