Comment 1 for bug 1899392

This is tricky because you could envisage in the general case that not all storage backends would allow the allocated size to be changed post deploy. And if they did, could that be done in place or would the volume need to be stopped and/or detached first etc. I think for now you'd just need to spin up a new unit with the desired storage and run a charm action to migrate the data across and then remove the original unit.