Set of subscription properties that can be updated. Each subscription property consists of a name/value pair. Available subscription property name is subscriptionQuantity. SubscriptionQuantity is the billable quantity of the subscription.For Office 365 subscriptions, the billable quantity is the number of user licenses. The quantity can be increased, but can only be decreased if it was increased in the past seven days. The quantity cannot be decreased by more than it was increased in the past seven days.