Well, I know that officers do still use these type of stations at weekends, nights as somewhere for them to use as a station for breaks, using computers ect and to remain in the area rather than travel 15 miles & take an hour to turn up to an incident ie your depot.
But 999 call which takes 1 hour before officers arrive is unacceptable & 4 times in 2 months is very either unlucky or your being targerted.
1st time, ok 2nd, concerning, 3rd. has no improvements to secure the depot been made???? 4th, something which needs comparing with other 3 and seeing what is similar/the same, and sorting out !!
But someone from the depot like a manager, needs to make complaint about the response time and have the issue brought to the attention of the relevant person who will do something about it.
Out of interest, what police force is this