You may get an email from Nominet the UK domain registry.

They would like you to buy the .uk domain to match your or

If you have a or Domain you have sole rights to register the .uk version.
If you wish to purchase the .uk domain within the next 2 weeks, the registrant contact has to be exactly the same as your domain. If they are not the same the registration will not go through.

For some reason the majority of .uk domain registrations have failed due to not being an exact match.
We can attempt to register for you but if unsuccessful now, we will have to wait a couple of weeks when it will not matter if the contacts don’t match exactly.