::::: Yes: 
 :::::* Keep Royal Ordnance Factory for the history up until privatisation. 
 :::::* Recreate Royal Ordnance but refocus it on the history from the intention to privatise until the dropping of the RO Defence name, i.e. remove duplication with the above article. (It can be summarised and linked via {main} or {see also}). 
 :::::* Keep BAE Systems Land Systems Munitions but, as you say refocus it on the recent history. 
 ::::: Woops, I see the point about RO Plc it may still exist as a (dormant) company. Your idea of dropping of the name RO Defence and the formation of BAE Systems Land Systems works well for me. 
 ::::: RO Plc, it seems had four subsidiary companies, RO Ammunition, etc; the ex (ICI/IMI) Agency Factories were brought "in house"; and there were site disposals, so there is plenty of scope for a separate article on RO plc. (BAe owned and/or had a joint venture with the Trafalgar House (company) to redevelop surplus sites). 
 ::::: Thanks for the reassurance, it is not always possible to work out aims & objectives during a change-revert-change cycle.