When does the insurance company report the EVB/insurance to the registration office?

Hello together… The following case: My current car insurance runs until 23.01.2020 and I have already terminated it. I already took out a new car insurance (A) in May which should run on 23.01.2020. However, I have today by fax revocations (is also in order since no contract has been handed over and thus the cancellation period does not yet run). Also today I have taken out a new insurance(B) which now really run from 23.01.2020 sol l. Question: When do the new insurance companies report the EVB to the registration office? Not that now Insurance A has already registered a number that is valid from 23.01.2020 and it now also does insurance B and then problems arise? Or do the insurers only report the number shortly before the start of the insurance and I don’t have to worry about it? Can you ask the registration office for such a thing by phone or do you have to come by personally?