I somewhat dived in to posting comments without really introducing myself, which I think was probably a bit premature.
So just to say that I collect GB mainly Victorian, and especially the different postmarks used at the time.
I also have a Commonwealth collection with more interest in New Zealand and Australia. There is also a European and world collection in the background and I do Railways as my Thematic interest.
I belong to two local clubs in Kent and use
ebay occasionally.

Some Liverpool postmarks, one with the N (for North Liverpool) reversed, with a '4' on its side, and unusually a '466' in a box inside the bars.

Watermark variation where the wire original has dropped off and a simplified replacement made and fitted.
Newspaper Branch postmarks following the Stitt Dibden List, these are also in the Curt Fernau booklet.

A few more of the NPB postmarks, some not listed as far as I know, but still loooking!
Hope you find them of interest. I am currently trying to build up the usual country wide Duplex postmarks, and also the London types.
Best wishes to all.