https://www.popularmechanics.com/military/aviation/a30186638/b-1-bomber-flying/ (Article from 2019)
“The U.S. Air Force may soon have to restrict one of its bombers from a key mission profile: flying low. The B-1B Lancer bomber fleet is growing old and the Air Force is considering restricting its ability to fly low, which is reportedly hard on the aircraft, in order to keep the big airplanes flying.”
I saw something yesterday evening that looked like a comet in the sunset sky, but was pretty sure it was the contrail from a high altitude Plane. Still, odd. It was the only contrail in the sky.
AF brass keeps on keepin' on having the same old problem they've always had with operating all those "too old" aircraft: Maintaining and occasionally updating effective machinery is both efficient and economical...
But it ain't half as sexy as an entirely new airplane. (Not to mention you miss all those big feeds, even bigger kickbacks and high dollar jobs after retirement from said AF.)