Any ideas what an Upgrade fee will look like?

For future upgrades to Resolve and definitely after version 20, it’s been hinted that there will be a modest upgrade fee to any new versions.

Any ideas on what this new upgrade fee may look like before you have to pay the full licence fee for any missed update cycles over the coming years?

It has only been hinted at by Grant as a possibility in the future. It is more likely to be for specific add-ons rather than Resolve itself. No one knows if, when, and what fees there might be in the future so speculation is pointless at this time.