Yes, they might not see the point in replying until they know if they are going to be MDR designated. And they may be so overloaded with clients who need MDD renewals prior to May 2020, they don't have the resources.
Another possibility is that they don't want you as a client under the MDR. There are going to be too few NBs and too many potential clients for some time to come. Under these circumstances, most NBs are going choose large clients over small ones.
Another possibility is that they don't want you as a client under the MDR. There are going to be too few NBs and too many potential clients for some time to come. Under these circumstances, most NBs are going choose large clients over small ones.