auto-translate from Russian:
The same story. I managed, after changing the region, to get through to the British support service, even attach a check to the application for updating the purchase date, but there the specialist said that he did not understand the check, redirected me to Russian support. The Russian support said that they could not carry out such operations for some time, they are limited in this functionality.
I don't understand what to do with this, I wrote to Apple feedback, but they are unlikely to help there either. I understand them too, since they do not want to bear the risks and service where they are not represented, but it is not at all clear what ordinary users who love and use their equipment to do in this situation.
I will also be grateful for any advice on this matter, namely for self-reassurance, and not for the need to contact the support under warranty.