[JAS84]

So 15 will be doing more than just changing his jumper! When the Doctor first took Rose back in time in The Unquiet Dead (episode 3 of the revived show), Rose dressed in period costume, but the Doctor wore his usual leather jacket, protesting that he'd changed his jumper - different coloured jumpers under the jacket was the only costume change the 9th Doctor ever did. He never wore period costume, unlike 15 who clearly is in appropriately period costume here with that afro wig.