You don't need anyone to oversee your HRT. The GP can do that perfectly well.
My GP has always worked with me to do that between the two of us. Yes there have been some mistakes made, mostly because I refused to let him do my bloods for quite a time, but we have worked together to solve them and the bottom line is I am still alive and fighting fit!
I honestly don't understand why any of you girls let the clinics hang on to you postop. Ok I wasn't an NHS patient and in any case I went my own way, but Alison was NHS. The day she walked out of the hospital postop - she discharged herself from any further contact with the clinic.