Hi,
Tintin Hey ? That smells very Belgian !
As far as I'm aware off no such agreement existed. Let's indeed not forget that about 6000 bombs were dropped on Brugge, killing 123 civilians, wounding 243 and destroying about 700 houses and homes. But there was not much of military value as a target in the historic center of the city...
Most important target was the Brugge harbour and the installations for the U-boats, torpedoboats and destroyers. Of course there were a number of other interesting targets such as the station, some factories and ammo dumps, but all were outside the city as you probably know.
In the center only the HQ of the Marinekorps Flandern, an important Lazarett, some workshops, carparcs etc.
On certain moments the harbour was almost bombed daily. Never was a success however and only minor damage was made. Bombing was after all not very accurate and some aerial photo's show bombs exploding hundreds of meters away from the harbour.
Best from Regulus