Effects of a VPN on throttled network and more.

Heya there so I don't see any posts on throttling anywhere lately. Everything is outdated! It seems like everyone has given up on this kind of thing.I was surprised to see my upload speed was constantly high (40-50mpbs) on hot spot shield yet download shot up and abruptly returned to throttled speed. So what's going on here? I feel like a packet gets sent by the phone when it first connects that then verified that my account is throttled. Hence why it's fast for the first second then it dips. Any info on this? And also the upload speeds?

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