Tbh, it took about 18 months from referral to actually getting my op date, and along the way I felt like I was trying to run up a down escalatpr. My last test (ECG) was back in March and I heard nothing for a month, so called and they said they were rearranging departments in the new financial year and to call back in May. So I did, and they said to call back in June. Kept calling and calling, leaving messages every day to call me back and they never did.
In the end I emailed the PALS service at the hospital and complained, said that I felt like I was being ignored and it really wasn't on. The next day I got an email back apologising, the following day I got a call from the consultant's secretary and by the following week I'd got my op date!
I'd recommend making a log of when you call and if you speak to someone or if you leave a message so if you do need to contact anyone about it you have a record of how hard it's been!