at The Roundhouse, London January 29 1978.
Maybe he'd got a second strat by that time? Is that really from 1978? I would've thought it was around 1980, because of the jacket.
no it's clearly from roundhouse january 78, there are others pics avaliable
and it's clearly the maple strat (serial 80470 ) more info here : https://www.mk-guitar.com/mark-knopfler-gear-database/fender-stratocaster-1962/
the pickguard is custom made. You can see the volume pot is not at the exact same place than on a standard strat pickguard
but what is rare is to see the white knob
some weeks after this date you often see it without knob (like in Rockpalast)
What I always found interesting in these photos, besides the knob, is that he is using a Musicman amp, when it is said that he started using Musicman amps in October 1978, which made me question many times if this photo is really from Roundhouse January 78, since, before October 78, he is always seen using a Fender amp and Marshall cabinet in photos and videos of the band.
good point. But in general, infos on the Getty site are accurate because of copyrights. So I think it's the exact date. Maybe he had a musicman amp just for talking heads tour in january ? 
Personally, I have noticed several inconsistencies in dates on the Getty website. I still believe that this photo is from a show between October and November 1978, although at that time he was not using the Maple Stratocaster but the Rosewood. I once tried to see what amps Talking Heads were using at that time, trying to see if they were using Musicmans, because if so, then they could certainly be borrowed, but I could not find any photos of them using Musicmans at that time, only Fenders, like Dire Straits.
Check out these photos.
Talking Heads Jerry Harrison at The Roundhouse, London January 29 1978. (Photo by David Corio/Redferns)
