If you are on Facebook, the private group “15th Army Air Force” is exceptionally helpful. Also, there are WW2 squadron and bomb group monthly unit history records available at the Air Force Historical Research Agency. You can search the unofficial database at airforcehistoryindex.com and then request electronic versions of relevant records by IRIS number (their in-house catalog system). You can also do research in person…they are located on Maxwell AFB in Montgomery AL. (This is the official archive of the USAF. They are not staffed or purposed to do look-ups. Read the guidance at the site above and on the AFHRA website: https://www.afhra.af.mil/ ) Recommend you start with the Facebook group.