This is an excerpt from a post by the mighty Winesinger on our old forum.

Every other week will be rift week and we have proposed doing rift on 3 days. During the week

My suggestion for our rift days is, Friday evening, Sunday All day, and Tuesday evening. I think these days are a good choice becuase we will get a break inbetween rift days to restock or sell loot. Also I believe this allows some of our kin with different schedules to tag along for 1 or 2 of the runs.

everyone post on that forum for now what days you can be available and would like to participate in running the Rift.