A number of Doctor Who fans noticed that Peter Capaldi, when he first came on stage after the announcement that he would be the next Doctor, did the lapel grab that William Hartnell sometimes did. It was almost certainly intentional.
As we reach what would, if the time lords’ limit on regenerations were enforced, be the Doctor’s final life, and as we have a return to the role being played by an actor who is the age of the original actor when he first played the role, this echo of a classic Hartnell mannerism is fitting.