Richie and Eddie watch The Power of the Doctor (Spoilers) 

They did change in the very first regeneration though, from Hartnell to Troughton. However, I don't think that influenced this...

Considering the clothes didn't change when the Doctor regenerated into the Master, I'm assuming this was an intentional thing.

@@CtaEverett23 Definitely, 10/14 is definitely surprised the clothes changed, it’s got to be intentional

@@NickHoad seconded.

there's a massive theory going round that it won't just be Tennent making a return, there will be smith and Capaldi as there going to be wearing the exact costume although slightly change over time (loosing the coat) hence the reason its not the 10th doctors costume more of a mix of 11 and 12s too as were getting 3 specials, I believe so one for each respected doctor worth a watch ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-JZEpgUgoeLg.html