I had RT and hormones about 7 years ago.
As you are still on bicalutamide, then you have had about four months of HT and you should be fine for starting RT. The implants are a different way of delivering HT, but as far as the cancer is concerned either way works.
PSA and liver tests are not necessary at this stage, and if something ain't necessary, it is not going to get done on the NHS. Though it would be nice to have the CT scan results, no news is good news
Sadly in today's NHS you need to manage your own treatment. 'the squeaky wheel gets the oil' describes the situation well. If you don't complain you will be ignored. I would suggest you ask for an appointment with your GP to talk about the breast pain and fatigue, it will then be obvious to him that it is the HT and hopefully he will write to your consultant to address this.
The side effects of the implants are different to the side effects of bicalutamide, so you probably should make a fuss about switching from one to the other.
You're going to have to keep posting on here if you want help. None of us are medically trained, but we can probably point you in the right direction for what questions to ask the specialists.