As per communications sent out some months ago, yesterday we switched all remaining https://clientsuk.appitierre.com/{instance} based sites to the new https://{instance}.evolveauthoring.com format.
If you are trying to access your Evolve instance and finding you cannot, please check you are using the correct URL format as the first step and update any bookmarks or links that point to the old format.
If you are not receiving Evolve communications please check your spam folders but also in your Portal account: go to Portal - Login (in Evolve go to Account Settings > My Account) and once in portal to Accounts > Contacts and check and edit/add those who are receiving them.