It sounds like duff service from Openreach to me .... but you are right also, Zen could have pushed harder too.
I am in a serviced apartment with the wiring from my abode going to a DP point on the ground floor. From there it is an underground service to the base of the pole and continues to a DP at the pole head. My wiring had obviously been disturbed by an earlier engineer visit as I had no phone service immediately following his departure.
It is a gated estate with the console unit dialing up the apartment the visitor wishes to visit. While the call is in progress, a code entered into the phone can be used to open the gate. But without a working phone line, I am completely stuffed. Amazon ordered Christmas gifts could not be delivered until my phone line was restored. Those gifts eventually arrived yesterday (29th).
I should point out that the native mobile signal is pretty poor here; forcing me to have a sure signal device but with no broadband service that doesn’t work. The attending engineer, Harry, had my mobile number and could have tried to make mobile voice contact or used SMS stating he had a problem completing the job, but obviously did neither as any messages left would have eventually popped up on my mobile once I had a signal.
You are right that I suffered a pretty poor service from both Openreach and Zen causing me no end of stress and extra expense over the Christmas holiday period. Zen claimed there was nothing they could do to expedite the repair and I am left with no entitlement to compensation from either company. Zen may offer a gesture of goodwill payment and will let me know once the offices are open in the New Year. However I got the impression that it will only be for a few pounds.