What will happen in Backdrop 2.x?
The lifespan of Backdrop 1.x has been extended several times as the lifespan of Drupal 7 has been extended. Initially, our goal was for Backdrop 2.x to be released at least 2 years after the end of Drupal 7 support. Our hope was to give Drupal 7 site owners the time they need to both move to Backdrop, and prepare for the first Backdrop major version upgrade.