From early 1942 till late 1943 the only 2 units operating the A-20/Boston they were 89th BSqn 3rd Attack Group and 22 Sqn RAAF (not counting 18 sqn NEI as they only had A-20/Bostons for a couple of weeks) , the 89th brought from the states approx. three dozen A-20A's these a/c were actualy operated by them in the states and I have photos of these a/c in the US still with the red dot in the star and red and white rudder strips all these markings removed before New Guinea at approx the same time the 89th were forming up in Australia and getting organised for New Guinea (Mar-May42) 22 Sqn was re equiping on the 22 DB7-B's intended for the NEI Navy but became refugee a/c in Melbourne Australia, around Aug-Sep 1942 as both sqns had started there moves to New Guinea, it was about the time the Legendary "Pappy Gunn" came up with his now famous straffers, he had planned the mods to B-25's and A-20's since June 42 and by September was into a full modification program the 89th Sqn A-20's were the first to be done with 4x .50 machineguns in thru the bombaimers glass position together with the cheek 4 x .30's then 22sqn got there 19 remaining Bostons similarly modified, though when it became known at RAAF headquarters Melbourne in late 1942 that 22Sqn had modified there Bostons into Straffers RAAF HQ "viewed with concern" that the Bostons had been so modified with out HQ giving the matter "due consideration", investigations failed to discover who had approved the modifications but HQ suspected that either the Sqn Commander or the senior RAAF officer in the area, but sent letters to the Senior RAAF officer in North Qld and the 22 Sqn Commander "in strong terms that they would be held resposible for this breach in orders" , as we all now know Pappy's mods to the A-20 and B-25 were some of the best war winning mods carried out to aircraft in the field in WW2 and latter marks of both a/c incorperated these mods and improved on them direct from the factory.
These approx 40 a/c with both sqn's then flew without replacements thoughout late 42 until by Aug 1943 both sqn's were down to approx 9 a/c each, the decision was made to convert the 89th to B-25 Straffers as adequate supplies of B-25's were available but no A-20's had arrived in theatre since 42, in Sep 1943, 9 x A-20C's became available and went to 22Sqn as replacement a/c, the last 9 remaining ex 89 sqn A-20A's also went to 22 Sqn ,these A-20C's were the only C models to operate in the SW Pacific and were unique in there weapons fit , they had 2 x .50 machineguns in the cheek positions instead of 4 x .30's and kept the bomb aimers glass with a strike camera mounted behind it with 3 x .50 machine guns mounted above the glass, these remaining DB-7B's, A-20C's and A-20A's kept 22 Sqn going until large numbers of A-20G's became available to the RAAF in Jun 44. 22 Sqn was the only A-20 /Boston unit in theatre from Sep43 to Jan 44.
89 th Sqn ran a mix of their few remaining A-20A's and B-25's until Jan 44 when large numbers of A-20G's became available to US units and the whole 3rd Attack Grp converted to A-20G's, their B-25's then went to the 345th Bomb Grp (Air Apache) , it was also at his time (Jan thru Mar 44) that the 312th and 417th Bomb Groups came on line with A-20G's, in a 5 month period from Sep 43 to Feb 44 the New Guinea area went from 2 sqns with approx. 18-24 wornout early A-20/Bostons to 13 Sqns with 120+ A-20G's with the 12 US Sqn's and 20+ DB7-B's, A-20C's and A-20A's with 22 Sqn RAAF.