Number of allowed connections refer to the total number of devices a user can have connected to OVPN at the same time. Every customer start with 4 devices initially.
In addition to these 4 devices, it increases by 1 for every year you've subscribed to OVPN. This means that by purchasing a one-year subscription, you will be able to connect 5 devices at the same time instead of 4.
The device increase is cumulative, which means that being subscribed for longer periods of time will increase your device counter even further. The increase also apply to monthly and biannual subscriptions. Once the cumulative subscription time surpass 12 months, it will increase by 1 for every 12 months you have been subscribed to OVPN.
Your current number of allowed devices is displayed on the dashboard when logged in.