I've done the update (from the GUI). Nothing reported, so I've expected that the update finished successfully.
But, at the restart, whatever I do it defaults to the LTS kernel. Manually selecting the current one works.
I've tried to update it with clr-boot-manager; I've tried to mount the boot partition, thinking that maybe the problem is connected to this; nothing. Even if the default kernel is the current one it keeps loading with the LTS one.
Actually I would say that the thing is not so dramatic, because I can set a small timeout and choose the correct kernel at start. The main problem is that if I start with the dock connected (a USB-3 connected to a shared Thunderbolt/USB-3 port), both the keyboards freeze and I can't select anything. Hence I've to restart the notebook without dock connected; choose the correct kernel; connect the dock; start working. A bit complicated way to start the day (or the week).
Before the update everything was working. I was used to work with the LTS kernel, but since the previous update I've had to switch to the current (that on the Dell 9560 has some small problems, but I can live with them).