Twitter will start removing inactive handles on December 11th
In order to delete inactive Twitter accounts from those who have either not used it in some time or those who have passed away, Twitter is preparing its first large-scale account removal.
Though the account removal "will happen over many months — not just on a single day,” December 11th is the last day for inactive Twitter users to sign into the site before their accounts are deleted. That said, the newly liberated usernames (or "handles," as Twitter calls them) will not be available for grabs immediately. The timeline for these handles to be made available again has not been disclosed.