My dad was on a troop ship that landed in Brisbane Australia several days after D day. That’s when he learned about it. His only impression of Australia was that they were given mutton for every meal. That and the heat made everyone sick
He later landed on Luzon with MacArthur
My father was a submariner in the Pacific. He said that they were often fed a meat referred to as "lamb," but everyone figured it was mutton.
My dad served on USS Yorktown and USS West Virginia during WWII. The Navy bought untold quantities of mutton from the Aussies during the war. My dad was so sick of the stuff that by the end of the war, that he would not allow my mom to fix anything for dinner that had sheep in it. Wasn’t until I left home at age 21 that tasted lamb or mutton for the first time.