Hi @Nick_Yanakiev,
Sorry for the confusion earlier. I’ve done a little digging and it’s very likely that as a Hyperoptic user, you’ve been placed behind a layer of their carrier-grade NAT. That would explain the timeouts despite no additional modem/router on your end.
It’s an unfortunate quandary with Hyperoptic that requires requesting a static IPv4 address directly from Hyperoptic for a small monthly increase in your subscription fee, according to other ARC users with your same provider.
Other Hyperoptic customers attempting to port forward for non-ARC purposes have tinkered with additional workarounds, as on Reddit here. Feel free to follow their suggestions, but the team recommends the static IP route as a workaround for now. Rest assured that the team is actively investigating workarounds for carrier-grade NAT that will not require setting a static IP in the future, although that’s not an option for the 1.0 release of ARC.
In the meantime, you can review another ARC user’s solution to your issue here: Attention: Hyperoptic UK Uses IPv6 and CG-NAT [Solved - Request Static IP]