g7
Think carefully before proceeding once the Change is notified to the DWP there is no way back.
First, although you say your son's mobility is worse does he now meet the criteria for an Enhanced award? If you do not have a reasonable level of surety, proceeding could be a mistake.
Secondly, he must have had this new level of limitation for at least three months and be reasonably expected to do so for a minimum of at least a further nine months. With no firm diagnosis, it will be difficult to argue a prognosis to meet this criteria.
Lastly, in answer to your question. We do not have a guide for this as reporting a Change will result in a full reassessment of his claim, a new PIP2 and almost certainly a participatory assessment. The existing Daily Living and Mobility awards will be reviewed from scratch, our standard Claim guide covers this.
Gordon
Nothing on this board constitutes legal advice - always consult a professional about specific problems 
