The actual documentation with the explanatory notes for transitional claims for DLA/PIP, as far as I can see, does not say whether a termination of DLA and a new claim for PIP will be required, or whether there will be a migration process in the same way as existing IB claimants will be transferred to ESA.
There is a lot of pre-legislative information floating around at the moment, so it may well be contained in some other document which I have not as yet seen?
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