The myVEGAS Room Rewards Calendars now include dates through June 2015.
Please note that while the calendars have been extended, many of the Rewards still show a January 2015 expiration. If you want to use a Comp Room Reward for a stay after January, you will need to wait until the new Rewards with the June 2015 expiration are released. My guess is that should happen within a few days.