I think there is also a technicality involved. You can only upgrade to 500Mbps if you are in a 350Mbps area. If your area happens to be capped at 200Mbps, perhaps due to congestion or inadequate kit, you can't upgrade to 350Mbps let alone 500Mbps.
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Hub 3.0, TP-Link Archer C8, TP-Link TL-SG1008D 8-port gigabit switch, V6