Was always a big fan of these even though they were not authentic being made with flaky pastry and no crimping at all.
When Hagenbachs was sold to Thurstons ( or to another bakers then to Thurstons, can't remember exactly) the recipe was retained.
And when Thurstons was sold to Greggs I believe they kept the same recipe for some time too, probably only in Yorkshire though.
Now Greggs sell a Cornish Pasty that's a bit more like the real thing and no doubt exactly the same at all their outlets but I still miss the Hagenbach pasty.