Japan on 6m?

In the first few weeks of June the 6m path from western Europe to Japan opens up regularly. This is a very long way. I recall a few years ago copying several JAs on 6m JT65. Personally I think this is indeed E layer propagation but not Es. I think it has something to do with E layer ionisation due to noctilucent clouds which form about now. Signals are usually weak and there in the early morning. This is a regular thing.

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