Above quoted T Letter 334/11 say this:
For the majority of personnel the introduction of Scheme Pays will have little impact. However, a small number of sqn ldrs and above leaving the Service on or after 11 Aug 11 who may have incurred a tax liability need to be aware of the option as they need to elect Scheme Pays before they leave.
whereas DIN967_2011 says this:The impact of these changes will depend very much on individual circumstances but it is most unlikely that any Other Ranks, or any Officer below OF 3 (Major and equivalents), will be subject to a tax charge.
Hmm, not the same thing...