In most cases, men were selected who had previously held non-commissioned rank in any of the armed forces or the USC.

The filling of senior NCO posts in this manner did have a drawback in that many men of comparatively young ages who had considerable years of service before retirement or promotion created a "promotion block"[8] Many of the men had previously served with the armed forces and, as a result, were given rank immediately.

[9] This led to a complaint from the chairman of the Ulster Special Constabulary association who claimed that: in 3 UDR preference for promotion and appointments was being given to Catholics.

[9] In some battalions where former special constables were in the majority, they were the ones being given a promotion and it could equally have been claimed in those cases that Protestants were given an unfair advantage.

Battalion Headquarters were located at Ballykinler Army Base which is also home to Abercorn Barracks where another British unit would be on a 2-year posting.

[11] Woods had won the MC with the Royal Ulster Rifles in Palestine during 1938, at that time he was the youngest holder of the award.

Where possible accommodation was sought in army bases although the old Ulster Special Constabulary platoon huts were vacant and available.

[13] In 1989 the battalion recorded over 900,000 man-hours of duty and the notable success of, in a joint operation with the Royal Ulster Constabulary, discovering a "highly sophisticated" arms factory which turned out homemade submachine guns for a loyalist terror group.

[20] In 3 UDR the most senior officer killed was part-time Major Ivan Toombs, assassinated on 16 January 1981.

Seriously wounded in a previous attack in 1976 Major Toombs was a former member of the Ulster Special Constabulary with 10 years experience who had joined 3 UDR at formation.