(25 May 2021, 8:53 pm)L469 YVK wrote Don't forget, the 21 is GNE's 'flagship' route (or one of them) so would no doubt be a good candidate to receive the newest vehicles.
And also don't forget that before the Hybrids, it was running around on ex-London B7TLs, before being replaced by even older ex-London B7TLs...