BTW, Great Britain's economy tanked after the FIW to the point that even though they came out with the New Short Land Pattern Musket, they did not make them in huge numbers for a while after sealing the pattern.
British Ordnance also made a habit out of assembling older locks on hand from inventory, into complete guns before they used new Locks - even at times when the lock styles had changed. Once they used up the older locks, then they put the newer pattern locks on the new production guns. That is why we sometimes see anomalies, different from the Sealed Pattern, in the first production runs of newer pattern guns.
Gus