Thanks all - there was contact made but I think her harness took the hit. Had they been off-lead it would have been totally different. We're in London so tracking the address will prove difficult but at least I'll know to cross the road and be well out of the way next time! We were very grateful to bump into several lovely dogs and owners after this (usually we actually rarely see any to talk to on our weekday walks) so TerrorPup got some play in as well as friendly calm interactions.
Had this been a puppy (we are 18 months so I am really pushing being on the puppy support thread!) it could have been really hurt, but also the impact on confidence could have been extreme.
We've witnessed plenty of snapping and snarling before, not necessarily at TerrorPup, but this was definitely a whole other level! And there was no greeting between the dogs at all, it just piled in.