Unlike OpenVPN, WireGuard use key pairs to authenticate to VPN servers. To alleviate some potential privacy issues with WireGuard's implementation of key pairs, our mobile applications automatically regenerate the key pair and internal IP address at a set interval.
By default, this interval is set to 14 days, but you're free to change this to anything between 1 day and 28 days by adjusting the slider. Once set, the key will be replaced at the set interval.
The Next Refresh on field displayed at the bottom of the screen shows when the key will be replaced next, while Generated on displays when the key pair was generated.