There are as of yet no plans for any group trips on Friday nor Monday. Seeing some individual plans, people are arriving at different times on Friday, and some not until Saturday morning. Likewise, many plan to go home on Sunday afternoon, and those still in town as late as the Monday holiday will be departing at various times.
One reason my hotel hopping is taking place in Alexandria and Crystal City is that it allows me to do some short points runs between WAS and ALX in each direction. Friday I am taking 95 WAS-ALX and 80 ALX-WAS provided both are close to schedule. That allows me to dump my luggage in my hotel in Old Town Alexandria in the afternoon before coming back to Washington to meet people coming in that evening. Should either one or both be severely late, I still have options of taking Metro or even VRE in lieu of Amtrak.
Monday morning the intention is to start my day on Regional 164 ALX-WAS, and then later in the day take either a Regional or Acela home in the mid-afternoon. No VRE that day but there's always the Blue and Yellow Lines.
As for meals together for those in town Friday evening and Sunday evening, I think that can just be played by ear as there is no idea exactly how many might be involved or what their other plans might be.