hahahah yes. BGP IS TEH SUX()R!!@!@. its making my packets go SLOW!@>!@>...
Just to clarify, BGP is not a link state routing protocol. It has no knowledge of congestion on a circuit. A net eng must modify the configuration to prefer or deprefer certain links to avoid congestion. However, if you're peaking out your circuit it could cause the BGP session to flap which would remove the congestion until it reestablishes the session. Yes thats a bad thing.
These config changes could happen anywhere between the source and destination and change traffic flows. Managed.com could very well be trying to keep 95th percentile usage lower by altering their BGP announcements.