I was more amused that the thing JJ's been joking about for years may actually be happening... O.o

From the news article though it looks like it's less going to be part of the anniversary and more likely a Children in Need special or something Peter Davison is cooking up for his own amusement.

In most circumstances I agree with you, but since it is his own father that he's (possibly?) playing I'm sure it wouldn't be done disrespectfully, but more as a tribute.