What's the max speed for this router?

Since unifi is upgrading my package to 500 Mbps and if this router cannot support 500 Mbps I am thinking to downgrade my package to 300 Mbps

https://www.asus.com/Networking/RTN12HP_B1/specifications/

From here it says 300 Mbps WiFi but WAN is 10/100 only. Since our unifi modem send data to this router via LAN does that mean the bottleneck is 100 or 300?

This post has been edited by LovelyPotato: Jul 15 2018, 08:44 PM