the old girl was never intended to do this, and so it is NOT acceptable!
(Perhaps not absolutely exactly)
Possibly no one at HBC expected that an operator would adopt the practice.
IE: No one at Hawker ever intended the old girl to do that.
we are not in a position to comment on it's acceptability.
IE: On your own bud.
But glad you got it sorted. Hawker would certainly not cnsider themselves liable for any damage caused due to the actions you describe and surely neither would the insurance. The operator would be loony to continue the practice after you face them with your information.