all at mister.red festivals (SW England & de Ddywrain Cymru) is as up to date as of March 1st - least ways those that have websites and have updated with 2018 info.

eg there will probably be a Gwyl Ifan in Cardiff but IME their info is usually JIT (just in time)

map.mister.red gives a clearer picture if you are limiting yourself to a locality. Though it includes Clubs and sessions. Click in the area of interest and see what it shows.

As I always say "let me know if you have specific knowledge and can update me"