So I think we need a single party (or coallition) with sufficient numbers to convincingly pass legislation either way. At the moment, we're in a complete stalemate because neither side have a large enough majority to either stop or finialize Brexit. I honestly think Labour are withholding a GE becuase they believe they will lose, particuarly if there's some agreement between the Brexit party and the conservatives. At the moment (especially in the North of England) we see MPs voting against the majority of the constituants views in the refferendum - a GE is likely to unlock that if the aforementioned Brexit Party / Conservative agreement can be made. Personally I think we'll be in this stalemate situation until another GE is held, and if the conversative / Brexit Party agreement isn't sucessful, there's no clear way forward at all.