See here for an article from Shepherd + Wedderburn on the interaction between Demand Side Response(DSR) and REMIT. The article refers to the recent REMIT Q+A which clarifies that a DSR contract is reportable under REMIT. This means not only that the parties must report, but also implies that the contract is subject to the inside information and manipulation provisions of REMIT. The parties would also need to register as market participants.
These considerations will also need to be taken into account as the market changes in the new market design announced in the “Winter Package” are fleshed out.