yung working bypass lang naman na VPN for pisowifi is yung port 53, naka open kasi yan sa lahat ng pisowifi system kasi hindi gagana yung redirect on connect captive portal feature nyan pag walang working dns server.
work around dito is add ka ng additional firewall rule na redirect mo lahat ng port 53 traffic to lets says google dns like 8.8.8.8 or 8.8.4.4, much better kung may sarili kang dns server like pihile or adguard. after ko ma apply sa firewall rules yan ng pisowifi system, effectively patched na yung bypass with vpn.