Dan — Regency / Georgian styles have been in almost continuous production since they were first made. Here in the UK they were certainly made in C20 by Richardson, Stevens & Williams, John Walsh Walsh, and others. They were rarely marked — the antiques trade didn't like it!
Glass screw tops on condiments are comparatively recent, probably dating from some time in the '20s or '30s, and then for fitting with bakelite and metal lids. Glass screw lids on condiments are more recent: I guess only within the last half century.
There is also a geographical puzzle in your condiments. The Georgian style was the province of the Stourbridge and Birmingham firms I've mentioned. Whereas glass screws were quite definitely the province of the bottle and jar makers, of which the largest and most innovative were to be found in the glass town of Barnsley.
... and apologies. I don't seem to have answered any questions — just introduced more.

Bernard C.
