Github now has a 'Organisations' feature that seems better suited to what we are doing.
Accordingly, we've created an organisation 'openvehicles', and migrated the four main repositories to that new organisation. The github URLs are now:
https://github.com/openvehicles/Open-Vehicle-Monitoring-System
https://github.com/openvehicles/Open-Vehicle-Android
https://github.com/openvehicles/Open-Vehicle-iOS
https://github.com/openvehicles/CAN-RE-Tool
Looks much nicer, and the most important point is that organisations can have multiple owners.
Supposedly the old 'markwj' repositories will continue to work (and be redirected).