Update/reinstall OS of deployed machin with retaining some data

Hi,
I am fairly new to the MAAS and still on the stage of reading documentation.

I would like to ask is it possible with MAAS to upgrade or even reinstall OS on the deployed node, but keep for example /home directory ? For

And related question could user of the node perform an update from Ubuntu 16 to 18 ?

Or node are designed to be stateless and this kind of data retaining is against MAAS design?

Thank you for you time and answers.