I would not have said, looking at the description, that this role is in any way related to Chilterns' traditional 'Train Manager' role which is primarily servicing the (dare I say) non-DOO requirement of dispatching the service.
It appears, to me, that this role is solely catering to the primary needs of 'Revenue Protection' and 'Customer Service', extending across the station / platform / train environments.
So my history is a little hazy and will need to look some things up, but, weren't the RMT against this type of role being enacted at SWT back in 2018?
Or, maybe a similar story , or situation like a few years ago, when Edinburgh Waverley, to Bathgate, went Driver only operation, due to its extension, from Glasgow Queen Street Low Level to Edinburgh Waverley via Airdrie,
Similar Story on the then new Scotlands similar East West link on Scotland.
1. Glasgow Queen Street low Level to Drumgelloch driver only. Class 318/320
2. Drumgelloch to Bathgate brand new.
3. Bathgate to Edinburgh Guard dispatch Class 156/158/170. Converting to Driver Only operation. But guards was given more services to work elsewhere.
East West very similar.
1. Oxford to Bicester Village is driver only class 165/168
2. Bicester Village to Milton keynes brand new.
3. Milton keynes to Bletchley, in a guard operated area, but on class 730/350 for example, but the distance a lot smaller , from No 3 , above in this post, As explained above in the scotrail driver only extension in Scotland on its Glasgow Queen Street to Edinburgh Waverley line.
Very similar situation, its looking like dtiver only operation, maybe how they got this through on Scotland on this line, back in time,
They have just done it here in England on the new East and West Line.
Role similar to Southen obs, with Station Customer Service included,
And mixed in with Scotlands on board, ticket checkers on its doo services, like they do , ie of a guaranteed person on board ablight a ticket checker.