To clear up your All patients page, you can remove redundant 'To manually book - 1st' patients from your list.
1️⃣ Filter by To manually book - 1st, and then select all, or select multiple patients individually
2️⃣ Select Cancel invites
There will be no text sent to these patients to let them know you are cancelling their invite. If you have not yet manually invited them (by letter, for example), you needn't contact them.
This has now cleared these patients from your all patients page: