Completely confused by PIP renewal process

Hi, I don't know what I shoiuld be doing about my PIP renewal, the DWP seems to have completely changed how they do things.
I first applied for PIP in 2016 and was granted a 3 year award. In 2018, I was sent a renewal form by post, the AR1, and was granted PIP till December 2020.
A month or so ago, I was sent a letter telling me my PIP was ending and asking me to call a number, which turned out to be the number for NEW PIP applications. The guy I spoke to was like a robot, reading pages at a time of information in a falt, mechanical voice, then asking me did I agree. Part of how my disability affects me is difficulty on the phone, especially processing large amounts of spoken information. The thing that really bothered me was that they seemed to be treating it as a new PIP application, not a renewal, despite me telling him several times it was a renewal not a new application. He just got impatient and said "Now I need to go back to the beginning again" and read stuff out in a dead flat voice and would not answer my questions aboiut why the changed process. I ended up in tears and unable to continue.
Today I received a packet in the post with a 28 page PIP1007 form to fill in, apparently an application to get the "How your disability affects you" form. The gov.uk site still says the DWP sends out the AR forms for renewals.
So I am completely confused about what I should be doing and why I'm not just being sent the AR1.