I was in 19C last week on a 757 and also had a Zone 1 BP. And zone 1 is nice for these seats because overhead space is harder to come by.
I think that is why they put the bulkhead rows (or those without storage underneath the seat in front in the 19C/757 case) in zone 1.
Bulkhead is usually zone 1, exit row zones 2 or 3.