Not sure there are any Fang Farrier's Apprentices on here however, I can confirm (having had a query regarding this qualification via the AFCO twice in the last two weeks) that civilian qualified DSAs still have an 18 month wait to join & still need the minimum GCSE's to be eligible for entry. (GCSE English & one other-preferably science at grade C or better)
(The required recruiting test score is also quite high- higher than most Engineering Technicians, lower than Nurses, AETs & Comms Techs.)
Once they have completed phase one training they still undergo DSA phase two training because of the different administration aspects in military documentation. Once completing phase two training, civilian qualified DSA's generally go straight into a dental practice draft without the need for journeyman's time.
Hope that helps any queries you may have with the training aspects.