Hello Panayiotis, thanks for posting on the Community.
If you have a licence you purchased via one off payment, such as through a retail outlet like Staples or Curry's, you can keep access to your account after June 30, 2023. Please note, older versions of QuickBooks Desktop, except QuickBooks Desktop 2021, have not had updates or security patches. After June 30, customer support will be limited for UK customers. This makes the risk of no updates even higher. We recommend that customers switch to QuickBooks Online or a different software provider in advance of the discontinuation so that they can remain compliant for tax purposes.