Abstract: A system and method of opportunistically unblocking channels in an ordered channel architecture. Masking logic creates masking parameters based on partial addresses received with a message. A subsequent message is imparted with the masking parameters to determine if it should be blocked. Based on the result of the comparison, the message is placed in either a blocked buffer or an unblocked buffer so that messages in the unblocked buffer may make progress independent of the message in the blocked buffer.