PIP claim and evidence

Also, does a letter saying it saying the importance of a home medical assessment for PIP have to come from a GP or could it come from a mental health nurse or psychologist?

I ve been so silly procrastinating but now I am taking action. I spoke to admin staff at my GP surgery who told me it is taking the 40 days to get all medical history to a patient. I am wondering instead whether to ask my GP to write a letter confirming my problems but she always seems too busy to take the time to carefully discuss such things when I phone and also I would have to trust her to explain my history well but then at least her letter would be current evidence. If I decide against contacting my GP for a letter and instead wait the 40 days for my medical records, can I have an extension on the time allowed to complete the long PIP form. I was going to put my claim in over the phone today, I got all my info ready for the phone call to DWP but then discovered this 40 day wait to get my medical records from the GP surgery.

Had a feeling I had read you can get an extension time for completing the PIP form if you have mental health conditions, Is this automatic. Your thoughts appreciated, thanks

You can have a 2 week extension, all you have to do is phone DWP and ask, they don't usually ask for a lot of details as to why you need it.