There appear to be two John Joseph Tivenan with MICs. Our man from the MIC is the RDF man. The service record for the E Yorks man shows they are not the same
1894 Born Highwood, Sligo.
1901 census at Croghan, Roscommon
1911 census in Treanagry, Croghan, Roscommon
1912 Oct 19. Leaves UK for USA
1916 Sep 26 Commissioned 2nd Lt in RFC General List
1918 Feb 23. R.Dub.Fus. Temp.2nd Lt. J.J.Tivenan , from Gen. List (R.F.C.), to be temp. 2nd Lt .
1918 Dec 10. 2nd Lt resigns his commission with RDF
1921 Jun 14. Accepted in England. Joined ADRIC with service no 2048. Posted to B Coy
1921 Jul/Sep Married in Cavan to Peggy Davison
1922 Jan Discharged on demobilisation of ADRIC
1922 Jul 28. Arrives in Canada from UK. His wife was Peggy, and their address was in St Johns Wood, London