Medical evidence disregarded by tribunal panel

I have received a statement of reasons for a recent first-tier DLA tribunal and I’ve read that the medical evidence I acquired from the appellant’s GP has been disregarded. Instead, the tribunal preferred the GP’s report that was requested by DWP as it was closer to the time of the decision.

The date of the GP’s report pre-dates the decision as it was used in the decision making process. This going to be the case for the majority of the time. I requested my evidence from the same GP as soon as I met the appellant for the first time, so couldn’t have acquired it any sooner.

The problem is that the evidences are somewhat contradictory; when the DWP asked the GP to comment on his ability to self-care, the GP remarked ‘OK’ as they did on his ability to get around, but when I asked the GP to comment on the descriptions given by the appellant of their care and mobility needs, the GP fully agreed with the appellant’s detailed descriptions.

I believe there is some caselaw about not disregarding medical evidence acquired after the date of the decision but am struggling to find it. Can anyone help? Thanks