Anyway just a tip for some firewall bypass using VPN sa telcos dito satin (blocking/throttle).
Never use their own DNS kasi isa yan sa nag momonitor ng inbound/outbound data mo.
Not effective yung dns changer ng openvpn kaya dapat system wide dns changer gagamitin mo. need rooted phone (android) or sa modem mo nalang palitan then use Amazon server since na 70% (approximate) nang hosted server ng telcos is sa amazon (hindi nila basta basta maibloblock yung server mo if ever)
To verify your connection if naka change na ng DNS. Use any DNS leak detection tool