How long does a PIP appeal take?

I was just reading on the newsletter that PIP appeals are currently taking an average of 30 weeks. I thought this might be of interest to people in my area - LIverpool. I rang this week and was told they are typically 35-43 weeks. At least from that I have some better idea. I had rung about another matter as I was concerned that a note I put on my letter sent early April had not been read. I had emailed in early May to check and although you get an acknowledgement to say you will get a reply within 7 days still not response 6 weeks later. I rang and my request of early April had not been noted but I am assured now it has.