Yes, this is not on a per aircraft basis license, so your 1 year purchase will provide you all cycle updates (they are monthly) for all of your hangar.
How the updates work?
A). xplane navdatabase. The fmc data manager app that navigraph provides will update the xplane general nav database.
More and more aircraft points their FMCs/GARMINs to read nav information from the xplane navdatabase. Once you update the xplane navdatabase via the FMS manager from navigraph all those aircraft are automatically updated as well because their read xplane database. No need to upgrade those aircraft databases. All FF 757/767/777 and all Garmin based birds fall under this category so far.
B). aircraft own database. Some aircraft uses their own navdatabase, such us Rotate MD, IXEG733, so you have to update their navdatabase held under their own folder structure. This is were the FMC manager app from Navigraph has to recognize them to properly update them. All existing xplane addons are recognized as of now, and if any new aircraft comes into play navigraph will surely include/support it.
hope this clarifies