After a bit more reading around (specifically here:
and
Udisks.service fails after latest update - #25 by dillthedog )
it would appear the error is caused due to using the Jessie staging repo? here’s my sources.list output:
osmc@osmc:/etc/apt$ cat sources.list
deb http://ftp.debian.org/debian jessie main contrib non-free
deb http://ftp.debian.org/debian/ jessie-updates main contrib non-free
deb http://security.debian.org/ jessie/updates main contrib non-free
deb http://apt.osmc.tv jessie main
deb http://archive.raspberrypi.org/debian/ jessie main staging
deb-src http://archive.raspberrypi.org/debian/ jessie main staging
am I on the right track?