There's only a year left to go before Sophos ends support for the on-premise Sophos Enterprise Console. Once this happens there will be no further updates to antivirus definitions and the level of protection provided will reduce with every passing day.
If you're still using the on-premise server-based solution you'll need to start planning your migration. LGfL schools can claim free licenses for Sophos Central with Intercept X Advanced which replaces Sophos Enterprise - via the form here.