New PIP review form posting time

I have the new PIP review form. I normally send things back signed for so I know it’s arrived after one MR form and documents “went missing”.
The new form says to allow 10! Days for postage, to use the envelope provided and NOT to send special delivery or signed for because it could take longer to get to the right person. It says to get proof of postage from the PO.
I’m not sure what to do now, I need as much time as I can get to fill in the form and the extra week makes a big difference. I’ve already had a 6 week extension

Is it still ok to send it 1st class signed for a couple of days before the deadline? Is this still the best way?

Thanks

Frankly Eggcustard, evil liars they are on this, just trying to make their lives easier at the expense of us nuisance disabled clients. Just like the "do not send xyz evidence" stuff. Send what you want to, how you want to. I always use at least signed for, print the tracking page and add it to the file. Worth every penny.
Best,
Denby

I send mine and get proof of postage.

I can only share my recent experience hopefully it helps;

1st review form i have returned via the Parcel shop using Royal Mail signed for . It was due on 4 Jul 25 . Posted on 2 Jul 25 and tracking shows it was delivered and signed for on 3 Jul 25.

The 2nd review form was returned using Royal mail tracked 24 was due by 29 Jul 25 , posted on friday 25 Jul 25. arrived Monday 28 Jul 25.

i have tracking confirmation both were delivered

I noted that the mail delivery centres were closed over weekend. So that something to remember if close to the wire.

hope thats reassuring that RMail are doing there thing well .... DWP mail ctr is a different matter
most import thing is have proof of posting if not tracking

update ....

I called PIP enq line today to check the 2nd one was in hand. The agent confirmed he could see the receipt and scan of the AR1 on system. So i am reassured . Ball is now in their court !