I think someone is trying to skin a dog, thinking it's a cat.  Let's not mix up combat pay exclusion (military only) and foreign earned income exclusion (ok to still have a US abode but you still have to spend enough time in a combat zone).

"Beginning tax year 2018, contractors and employees of contractors supporting the U.S. Armed Forces in designated combat zones may now qualify for the Foreign earned income exclusion (FEIE). To claim the Foreign earned income exclusion, you must meet the Bona fide residence test or the Physical presence test.  The Bipartisan Budget Act of 2018 changed the tax home requirement for eligible taxpayers, allowing them to claim the Foreign earned income exclusion even if their "abode" is in the United States."

https://www.taxesforexpats.com/guides/contractors-abroad.html