In some instances the leafing out comes after blooming. I have several in the cold hardy "Northern Lights" series - my very large "Mandarin" has no leaves to speak of yet but is loaded with buds. It'll be in full leaf once the blooms go.

The exbury azaleas usually do bloom prior to leafing out. If you want to prune the stems back to the next node, you should be fine in doing that. It will probably become more bushy rather than open. I like mine being an open plant so I don't prune it at all. Also, mine often grows new shoots from the roots too.

I rarely prune deciduous Azaleas. Usually there is no need to. I like mine a little open also.
Mike