It's a good idea to take estimates like this with a grain of salt. Schedules for spaceflight can slip with little warning (even this latest test was delayed by a day). And there's no denying that Musk's estimates are sometimes optimistic -- just look at how long it took Falcon Heavy to translate from a concept to an honest-to-goodness launch. The escape demonstration was the last major test before the crewed flight, though, so there isn't as much of a chance of delays as there has been in the past.