Everything about this board is from another era, starting with the white-on-blue lettering. It has been at least sixteen years since the city's name was officially changed from 'Madras' to 'Chennai', but this board still has not been updated.
It has been even longer - I forget when, but I'm willing to bet that it was at least twenty years ago - that the telephone numbers in the city were moved to seven digits. Maybe nobody has tried calling them for a while.
But somebody did tell them that their address had to be changed. Mount Road - on which this shop stands - was renamed Anna Salai sometime in the early 1970s; with that clue, we can conclude this has't yet gone into the 'antique' category, but remains merely at the 'classic' stage!