Updating software from App Store not available for purchased items.
The solution is to keep 2 separate AppleID accounts:


One for the country you used to live in, with a valid address for that country. Credit Card may be expired as it's not needed for updates.
Another for the country you live in now with your current details.


I've had a long email conversation with Apple re the subject, but they don't allow for purchase transfers between countries. They treat each country's store as a separate entity with no option to transfer purchases between.

Unfortunately this means, that in order to get an update for the apps which are attached to different AppleIDs you have to log out and log back in with different details. This is a bit of an inconvenience, but still cheaper than buying all the apps again.