Hi,
the requirement for having address in Denmark the day before starting education should be considered as a strict requirements, for which there can be made no exemptions.
However - registering an address in CPR (CPR residence registration) is not crucial for meeting the requirement.
It is also ok to change accomodation, and move within Denmark, but what the A-kasse will look at is, that the address you had one day before starting education in Denmark may be considered to be your actual residence. The address must also be considered as your current and usual place of residence.
If you have not been registered in the public address register (CPR) 1 day before, it is up to you to prove that you have been resident in Denmark.
It must be a real residence. A mailbox address or poste restante is not sufficient.
A landlord's statement that the you have rented a property from a given date may be sufficient proof of a place of residence.
But the A-kasse must make a concrete assessment in each case.
Best regards,
Anders, wwwa-kasser.dk