Amigafan wins, TUPE situation, Mr X. wouldn't TUPE across unless he was made management. My company promised continuity of service to client, my company over a barrel within days this new job appeared.
To make things more interesting, I've already been doing some things covered by Mr X impending new job for 18 months, is that long enough for 'custom and practice' to apply to job role? Management have just been made aware of my extra duties.