MRT list still current but depends where you are as not many mountains in Barnsley.
Go to say, North Wales, The Lake District or the Scottish Highlands and find a high point to sit and hardly a day goes by without one or more of the teams being called out.
During to recent floods in Cumbria pretty much all of the teams were out. Likewise in the Scottish Borders and then in the Highlands.
Busy teams like say Patterdale or Glencoe appear to be called out a couple of times per week if you are in the area. Most have websites listing callouts and some even describe radio equipment or location of repeaters. Bolton comes to mind.
Guess from Barnsley you may just get the likes of the Calder team or perhaps on or the Peak Dist teams but they are are not as busy as the teams in the mountains.