A claimant can request a SoR for all Decisions made by the DWP, however, the DWP only has to provide one if it can be shown that the Reasons have not already been provided, albeit in another form, we have had a number of members post in regard to the PIP Mobility review and I would be surprised if the DWP does not argue that the letter that the letters that they have already sent explain the reason for their Decision.
You can continue with the request but I would not hold your breath that you are going to get anything more from the DWP.
Gordon
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