Slitherine

You can find out what an upgrade will give your unit by selecting 'upgrade' and right clicking. But that only seems to work if an upgrade is possible right there and then. So is there a way to find out what (if any) upgrades are available to a naval unit at sea?

None other than counting the total amount of unlocked techs for the unit and comparing that with your units' tech levels I'm afraid. Will put it on patch list.