I have had the following link sent to me in respect of the new Optare Tempo SR on display at Coach & Bus Live today. Thirteen such buses are for trent barton to upgrade the Rainbow 4 route.
PS. Looking at the pictures it looks as though 'Rainbow 4' is going to be known as 'i4' in the future. Perhaps Apple should have registered a lower case i as a trade mark. Also the leather seats have gone being replaced by 1930s looking mocquette.