Bots can be setup to bet at a custom time, with custom staking plans and custom trade-out/hedge rules pre-event or in-play. Bots can bet in your own customized way based on your manual selections. Bots can also find selections themselves and be 100% automated based on your selection criteria and betting instructions.
Yes, Betfair can detect VPN usage if you are using a shoddy virtual private network. With a reliable VPN, such as NordVPN, you can get a dedicated IP, change your location, and use obfuscated servers. That way, Betfair shouldn't detect that you are using a VPN.