One of the more prolific tags around Halifax is what I have refferred to as YOOPZ - a consistently written, loopy tag which clearly contained the letters present.OPZ.
I found what seems to be an older YOOPZ tag, which on inspection, is POP*Z, ie 'PopStarz'. Sure enough, in hindsight, the little mark for the star remains present, if diminished. As always, once the meaning appears clear, I can't see in hindsight how I could have thought it was anything else.
Mystery solved - Goodbye YOOPZ, Hello POP*Z!
