First Utility give you the option to wait or have a call back (and they do!) or wait and while you're waiting, choose what style of music you listen to. Don't think I've been on hold for longer than 10 minutes.
Now fecking KCOM, bunch of.........
50 minutes waiting, then speaking to someone who said I had to ring a different number, rang that, waited, spoke to someone who told me they couldn't block a stolen phone number, nothing they could do till Monday. So I asked if I could perhaps ring EE direct and she said 'oh I suppose you could do that'. 3 minutes and all sorted with EE (excellent call answering by the lovely Linda)