I've just scanned several really sad Intranet websites.
"The RAF Leadership Objectives and Attributes" which are published as "Notes for the assistance of Reporting Officers in commenting on Leadership in Appraisal Reports" by the RAF Leadership Centre uses 'Followership'. It does not use 'Followship' or any other variation.
Operation MOLEHILL is now stood down. Those currently drafting letters of outrage to the Daily Mail are to cease. Those on Q are to return to eating and sleeping. Those retired are to reduce consumption of Worthers Originals.