The PMDG 777 deck and cabin crew does not like taking the shuttle bus when boarding. Even with v3.0.8 they still appear out of nowhere and walk to he plane.
In contrast the PMDG 737 and MS A310 crews prefer taking the shuttle bus.
To reproduce, just park the T7 on the EGLL south cargo apron around stall 609 (as per Navigraph charts).
Thanks