And if they don't want it, send it this way
I'd just add that there is little point telling CP CS about the cab work hoping it'll resolve things faster, that detail (useful to the engineer who actually visits) is almost never put on fault notes these days.
The most useful info will be a description of the fault, i.e. Crackle and a valid contact number for you.
If the CP insists on an appointment, no point in arguing the toss, just take the first going and ensure the CP puts 'please ring 0123 456 789 30 mins prior to visit' in their notes for Openreach.
If the engineer does visit,
then is the point to mention all was well till the cab uplift started.