In our E1 (9.1/AS400) system, there are four E1 Subsystem (1st one is E1Subsystem and rest of them(three) are timeZone specific E1subsystem)exists in Production .
Built update package with one custom BSFN along with other OL objects . But deployment is failing on three timeZone specific E1Subsystems) and deployment successful on 1st E1Subsystem.

If we excluded custome BSFN from build then deployment is successful on all four E1subsystem.