All intermediate Up2Dates must be applied. When you select installation of 8.300, the other Up2Dates will be applied automatically in order before 8.300 is applied. William has been recommending that 8.20x Up2Dates be applied separately, but I haven't seen the same issues - ymmv!
Cheers - Bob
Sophos UTM Community Moderator Sophos Certified Architect - UTM Sophos Certified Engineer - XG Gold Solution Partner since 2005
This is from the manual.
A note on "implicit" installations: There can be a constellation, where you schedule an Up2Date package which requires an older Up2Date package to be installed first. This Up2Date package will be automatically scheduled for installation before the actual Up2Date package. However, you can define a specific time for this package, too, but you cannot prevent its installation.
Thanks for your feedback, I think there is a glitch somewhere in that process that doesn't happen to many people. I had a similar experience with our demo unit.
Cheers - Bob
Sophos UTM Community Moderator Sophos Certified Architect - UTM Sophos Certified Engineer - XG Gold Solution Partner since 2005