It seems like, if you’re using just one VPN provider, it could potentially reveal your real IP address to connected websites every time the VPN server changes. Assuming that the VPN provider has no protection against accidental disconnection… Mine does. I normally have to restart the browser after a server connection loss.
I don’t know if there’s a provider or pooling client that automatically pauses activity and switches to a different random server. I can imagine that some websites might flag such as suspicious activity and either reject a connection or force you into endless annoying recaptchas.
An article on chaining VPNs: https://proprivacy.com/privacy-news/chaining-vpn-servers-double-vpn /