I think VWL119 that the notice said 10 double and 20 single deckers to be refurbished.  Thinking about it a bit more, that would cover the original DDs that are fairly tatty as well as some of the earlier VWLs, not sure how much 20 would cover ie from VWL x to what?  As the P&R is a contract service its upgrade and expansion is under a different funding mechanism, similar to if Cronin's or Kavanaghs won it.  I think in addition to the refurbs there is a separate project to paint buses, so the higher VWLs (149-157 as you identify) would only be getting a repaint.