It is recommended not to completely delete the rate from Mews; you can just disable it. You would also need to delete this rate from the mapping of Channel Manager and from the Channel Manager extranet.
But if you want to delete the rate completely, then you can do so. When you delete the rate and it has future reservations on it, the price of the reservation will not be changed. The rate is still shown on the reservation but there will not be any data about the rate in the system.
Any deleted rate would stay attached to any past or future reservation. The only difference will be that this rate will not be searchable in the reservation report if you want to search by this specific rate.
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