POST and Processing time for anything PIP.......

I had reason to call PIP last week regarding updating claim. I had been given an extension time for paperwork to be submitted, but then received a letter saying paperwork was due on the original date.
After that was cleared up the Adviser (Ben) happened to mention there is a 4-6 week delay with the Post Office. I questioned that he meant their office. Categorically not he said, the Post Office had told them this.
In that case anyone submitting paperwork is NEVER going to hit a deadline as you only get a maximum 4 weeks to get.paperwork submitted. That gained me another 4 week extension but I expect problems now.
Thought all you lovely people needed to be aware.of this info.
I'm inclined not to believe it but I don't trust them at all.

I was told similar when I called about a month ago although I thought it was a backlog with internal post system as hadn’t heard of any issues with Royal Mail.

I thought I had read somewhere, and have just googled it for confirmation, that the Post Office/Royal Mail has the contract for opening and scanning all the DWP post received. So the problem may not be postal deliveries to the DWP but the opening and scanning that they do.