I wish people would learn that the difference between static and dynamic IP addresses is literally all about how the end device is configured, not whether the address will change or not.
To be fair, it's not their fault. There's a lot of information on the web that says, switch off your modem, turn it back on and you'll get a new address. The problem is that while DHCP assigned IP addresses CAN change, they don't always change.
Furthermore when an end device is given an IP by a DHCP server. It is allocated for a period of time called the lease period. If a device disconnects from the network and then reconnects before the lease period has expired, it will be given the same IP address again and the lease will be extended. Furthermore devices always ask for an extension of the lease well before it expires.
Virgin Media issue 7 day lease times to devices on their network. This means that it's very rare for one of their IP addresses to change.
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