Presumably this means ad breaks between the sets a la PDC World Darts on Sky.
They have had breaks the last few years when BBC/BT Sport have shared the rights, usually in the early rounds they don't have any but the later rounds they had breaks after 2 or 3 sets but less frequent than the PDC breaks on Sky, in the Final the last 2 years they had breaks after 3 sets for BT Sport while Colin Murray and Bobby George did analysis.
Also on another topic the BBC at the end of next month are covering the PDC Champions League of Darts across BBC One & BBC Two so will they play uninterrupted or have breaks with analysis in between as when Lakeside was exclusive on the BBC only the Semis and Final had breaks and only halfway through.