That's right, Wedge Antilles has a wee cameo in Rogue One.The Rebel pilot whose quote 'look at the size of that thing' is the stuff of Star Wars legend, has a cheeky cameo that's harder to find than the robot Chopper!
So where is he?
It's not where, more of a case of 'hear'.
Wedge's character is famously played by English actor Denis Lawson. However, in the original version of Star Wars, Lawson did not do the voice work for the character, it was done by American David Ankrum.
This is where Rogue One's Supervising Sound Editor Matthew Wood had some fun with the movie. He decided to add a pretty cool Easter egg into the film and he needed David Ankrum to do it...
He asked David to come into the recording studio to some lines to be the announcer for the public addresses system the Rebel's base on Yavin IV.
I don't think I would ever had picked up with cameo Easter Egg unless it was specifically pointed out to me!
It was reasoned by the film's production staff that Wedge Antilles couldn't make a cameo in Rogue One because in ANH when he sees the giant Death Star for the first time he states in amazement the line we mentioned about, 'look at the size of that thing!' If he had taken a part in the the battle over Scarif, he would never had said that line in ANH and thus there would have been a continuity error in the movie.
Thus Wood, wanting to do the Easter egg, had to get Ankrum in for the voice over.
Extra for Experts:
Rogue One had many other cameo appearances including some familiar pilots...
Here's some trivia about Wedge
Fun fact, Denis Lawson is actually Ewan MacGregor's uncle!).