Why rollback, if one can avoid upgrading to a new kernel in the first place ? All one needs is proper warning, such as one finds in this forum. Of course, in
another thread, one is urged to update to a newer kernel for performance. In that same
thread there is a warning about the serial port not quite working. In fact, it gets stuck at the point at which ssh gets started and does not manage to end up in the command prompt like it does in Angstrom. Perhaps that' s a feature though, to force one to use ssh.
It would seem that, besides the small number of suitably qualified users, ARM devices are not quite similar enough to one another to allow relatively problem-free porting of software solutions from one to another. Hence developers end up getting overwhelmed.