Overpayment of PIP : date of recovery?

I have a client who claimed PIP in april 2016. At the time she was recovering from ankle surgery and couldn’t weight bear. She also has spinal / hip arthritis and a few other conditions that affect mobility and ability to self care.
Medically retired after accident at work and in SG of ESA.

DWP started watching her july 2018 following a tip off, and to be fair from what they have said she no longer appeared to meet criteria, although ive not received the video yet.

I think she got better and didn’t report it. She thought PIP was based upon your worst day (and we know it isn’t) so I think there is a recoverable overpayment here

DWP have decided to supersede from December 2016, stating she misrepresented herself. I have no idea how they came upon this date. She has had 2 PIP medicals and awarded EDL and EMOb both times. Medical evidence supplied each time, and muskoskeletal examinations by HCP contributed to the awards made.

Thoughts?

what’s the dates of the medicals?  what does HCP reports say?

i’d be inclined, subject to client’s actual instructions and sight of medical records, to appeal - which should at least get you the relevant paperwork upon which you can then take further instructions…..