I would say you are probably right !! Only one I found that fit was Edward Challinor,, who was in Staffordshire 1842 to 1867 !! But those backstamps didn`t match this one !! However he was in business prior to that in Burslem of which I found no identifying marks !! Overhouse Works I think was the factory name !! Most potteries go through a succession of marks during their production life !! Its possible that this EC was from that early era !! There is a Loe Bar off the coast of England !! I am not familiar enough with the English coastline to say if it had anything to do with the plate ,,,but Loe Bar may have been a pattern name if the design was a seascape !!