The IP reputation system is not handled by HubSpot directly, but instead by our CDN provider. We can look into situations with extenuating circumstances, but on the whole we will not make exceptions to our security systems as this can potentially compromise the security of the entire platform. This is particularly true when using shared hosting; making exceptions for traffic coming from a shared IP address can allow bad actors to abuse the exception.
In the majority or cases, IP reputation blocks (or other CDN based security features) will automatically clear after a certain amount of time without any malicious looking behavior. The best solution in this particular case is to transition to a dedicated IP (like you’re already doing) and wait a few seconds (a minute at most) if you’re running into security blocks.
If you find that you continue to consistently run into security blocks after transitioning to a dedicated IP, feel free to reach back out here and we can continue to troubleshoot.