None of us really know yet unfortunately. Hopefully we'll hear at least that much by 4/20.
Depending on who you ask though, some people have said you will be allowed to do the video chat on 4/20 for a trip on 5/20 and incrementally each day forward.
Disney has really not done a good job of informing us on what exactly their plan is and quite frankly I'm not sure if they really know what the plan is either other than what they have already told us.
It is like they're trying to build the plane while they're flying it and not doing a very good job at communicating with us how things will work. We know their intention (reduce the number of
DAS users and reduce the number of people using the
lightning lane) but thats about all we really know.