Complex sentence: RAFVR (T) officers involved in CCF or ATC Units may undertake extra training before becoming appointed as an Officer Commanding of their Unit, although this training is not compulsory for Officers associated with the CCF.
Split into simpler sentences: RAFVR (T) officers, involved in CCF or ATC Units, may undertake extra training before becoming appointed as an Officer Commanding of their Unit. Although this training is not compulsory for Officers associated to the CCF.