Hi
Thanks so much for your interest in the mug. The writing around the side is "Estates Times Every Week" and on the base, in addition to the mark, it is impressed: "With Best Wishes .... From Estates Times". I have found out from other ex-employees that it was definitely made as a gift for readers / advertisers, based on the invented character, Stackup, who they used in a strip cartoon in the magazine. The character was invented by cartoonist Alan Bailey, who published under the name "Kipling" - sadly Alan died a few years ago.
Re. the mark - it very difficult to get a good clear photo! I have attached 2 versions - one more or less "as is" with a bit of sharpening, and I've used an embossing process on the other one to try to make it clearer. I see what you mean that "H" is only one possible interpretation - the more you look at it, the more if could be a double " f ", or even two very stylised trees - with fallen leaves all around them. The possibilities are endless! I can't find any other marks anywhere else. Thanks again and regards