Given the fact that no registration change has been registered for service x34 (except for those relating to imminent changes this weekend), the suggested increase to a 20 min frequency will be at least another 2 months yet.  So the additional double deckers that South Shields are receiving will not be required for service x34 just yet (unless 19194/96/97 do get transferred), and therefore will be used on other services.  What is wrong with them being used for the x20 (permanently even?) Also service X20 is normally the 22050/67/70 operated which is the larger vehicle capacity so would make sense for those vehicles to be replaced by the 19641-47 batch.