embarrassed to report that I've actually been using two LR catalogs simultaneously. they are virtually identical but still need to be merged. my ? is whether to merge them first and then upgrade the remaining catalog to LR Classic CC or and i don't even know how to ask if there is a second option.
Probably best you merge them before upgrading then upgrade the merged catalog.
yeah, that's what i thought too. upgrading is easier than merging. thought i could eat the dessert first. thank you.