Re: Is the honey left over from winter "extra" that I can take?
Glad to hear your bees overwintered well, sounds like you are in pretty good shape. Your colonies have a lot more brood expansion coming up and you want to leave them with plenty of stores to make it through any extended periods of cold or wet weather this spring. Others may have different ideas, but here is what I would do.
Move your box with brood to the bottom. Above that, add two boxes with alternating frames of honey and empty comb. Leave the 4th empty box on top. Your bees will work their way upward and consume the honey as they expand the brood nest into the next two boxes. Later when the flow kicks in you will find new nectar being stored in the top box.
This has been an unusual spring so you may be able to get away with taking some honey from them. But it's surprising how quickly a booming spring colony can go through stores during a long period of spring rain.
To everything there is a season....