Shard Subscriptions are a setting in the GameGlass PC software that allows you to always have the most up to date version of a Shard with all keybindings pre-applied. For example in our official shards these will match the GameGlass keyboard profile available from within Star Citizen.
Alternately you can choose to set the toggle to a custom version of the Shard which creates a copy specific to your account in which you can edit all the binds and they will not change from your choices.
Only Shards added from the marketplace directly can become subscription by default. Any older copies default to custom to avoid loss of settings. If you would like to update an old custom copy to the latest default layout you can choose the reset button to accomplish this.
See our video guide for further details.