Weird issue with wireguard performance in one direction

So the last couple days I have been testing out wireguard to replace openVPN for the site-to-site connection between my home and my azure could development infrastructure. At my home, I have 1Gbit symmetrical FTTH and the azure DC in my city is like 3 blocks from my condo so the latency is about 2-3ms.

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The weird issue I am seeing is when testing throughput with iperf3 is:

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Home ------------->DC ~550Mbit/s

DC----------------> Home ~50-65Mbit/s

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Both systems have more than enough CPU power to push 1Gbit, I am using the official wireguard client for windows as the client in my home and the server is ubuntu 18.04LTS.

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Any ideas?