This sets the HDLC address used as the next-hop identifier for a route destined to the satellite interface, with valid range depending on the network mode, 1-254 in Small mode or 1-32766 in Large mode. The MIB notes this address cannot have 0x00 or 0xFF in the least significant byte, a specific hardware or protocol constraint that means certain numerically-valid-looking values would still be rejected or behave incorrectly on the wire, so an admin scripting route creation needs to explicitly filter those values out rather than just checking the numeric range. A value of 300 configured while the network mode is still Small Network Mode, capped at 254, would be an invalid HDLC address for that route despite fitting within the object's overall 1-65535 syntax range.