You can start your VPN business, but you may run into issues and cause your customers to conduct chargebacks, refunds or sue for not being able to reliably offe

You can start your VPN business, but you may run into issues and cause your customers to conduct chargebacks, refunds or sue for not being able to reliably offer services. If blocking/disrupting/unauthorized decryption of their encrypted traffic occurs in the future you should inform your customers of this issue so none of them are unaware. Now if it becomes illegal in the UK to offer any encryption services, require backdoors or lower grade encryption you may need to migrate your residence and business to another country to legally continue business operations.