We have Coppercoated from new & the keel is very rusty. I don’t think the keel was epoxied before copper coating. We spend the winter in the water and lift out for July/Aug when we return to the UK. I’ve arrange to have the keel slurry blasted, treated, epoxied & Coppercoated this summer in Preveza. The keel / hull joint will need raking out & resealing as well.
I’ll let you know how it goes.