(14 May 2021, 1:59 pm)ne14ne1 wrote Thinking aloud here again...... So are the Gemini1 Hybrids in London Euro5 then?
If so, does TfL not require all buses operating in Central London to be Euro 6, or if as long as they’re Hybrids are Euro5s permitted?
Anyway know?

Here is a link to the ULEZ website: https://tfl.gov.uk/modes/driving/ultra-l...ssion-zone which explains the requirements for vehicles in the ULEZ.

However all buses that operate on any TfL route now have to be Euro 6 or have been converted to be Euro 6 compatible (see this page on the TfL website: https://tfl.gov.uk/modes/buses/improving...tcmp=42923.)
so in answer to your question: "So are the Gemini1 Hybrids in London Euro5 then?"
No they are all now Euro 6 compatible.