ABT's delay in listing tour casts and the listing of other performances is their norm. I assume for DC and Oman, the delay in releasing casting has to do with figuring out which principal dancers will be available for those tours, as not every principal dancer goes on every tour since many of them have other performing obligations. Maybe some of those dancers' schedules for 2017 haven't been nailed down yet, or they're still trying to iron out conflicts. But, every dancer performs at the Met for obvious reasons. I would think their touring schedule for next year would be finalized by this point, but maybe not, so I'm not sure why no more performances have been listed yet. However, it's customary to see more performances added to their schedule as the months progress, so I'm pretty sure they'll be going to more places besides DC and Oman in the Winter/Spring.