The “A” and “B” sides were mainly directed at radio stations, knowing that record companies wanted to “A” side to be the main release but individual DJs would sometimes pick the “B” side as their favorite. Many records sent to radio stations over the years had the same song on both sides so there would be no mistake.
When they release the Re Kurd they are guessing. Once it’s out…then they know. Music history is full of B sides that eclipsed the A side.
So it had nothing to do with sales?