I believe, that all the lenses from the first batch i have, have a multilayer coating.. They were packaged separatelly, and one bag said 405nm, the other 400-720nm, but i kinda think they are the same. It was probably easier to give all the same coating.
I asked the new manufacturer to check which of their coating options would achieve the lowest reflections at 405nm. The lowest reflection coating would produce the highest transmittance for the lens.
It is possible, that their multilayer will have better propeties for 405nm, than single layer MgF2. In this case, the same lens could be used for reds.
If not, there will be a separate lens for reds.
Or is there another reason you ask about the ML coating?