Super VHF/UHF/SHF DX via noctilucent clouds?

In the next few months noctilucent clouds are often seen. There is a possibility that these are responsible for the very long 6m paths that regularly open from western Europe to Japan in the early summer. These openings are as regular as clockwork in the early summer, and then they just stop. It is a very long way on 6m and the conventional wisdom that this is multi-hop Es to me seems very unlikely. Last June, several Japanese stations were spotted on 6m JT65, even on my omnidirectional vertical.

See https://sites.google.com/site/g3xbmqrp3/vuhf/noctilucent