Probate Phone Line changes

Just been onto Probate portal and found the following message:
Probate: From Wednesday 14th February the Probate phone lines opening hours will be changing. The new opening hours are 9am till 1pm Monday to Friday. Webchat opening hours will remain the same.

I’m frankly pretty annoyed about this, the service is absolutely appalling and now they are restricting when you can phone them because they clearly cannot cope with the level of annoyed customers. The waiting time is already about 30-40 minutes to speak to someone, which will now undoubtably get worse. Is there anywhere we can complain do you think or should I just accept the changes and stop ranting about it?

I’ve given up trying to phone them - takes too long and they generally can’t tell you anything useful anyway!
I’ve started using the online complaints tool Complaints procedure - HM Courts & Tribunals Service - GOV.UK
which, more often than not, yields a result (eventually).