I think you will find that although they have the odd folkie on their working group, the event is organised by Gloucester council. They do have a website https://www.gloucesterbid.uk/gloucester-folk-trail/
but as far as other publicity is concerned, if that is in the hands of the council well.......

I have been before, but not sure if I have accommodation yet this time. As Mr Red says, it tends to be pub based venues mostly, but variety and choice, most of which can be within a fairly small central area of the city centre.