What's a dynamic hallway? It's a hallway "built in sections that can easily be swapped out with other things," Miller explains. "For example, if a mission calls for the player to be in a more engineering-type deck, we can very easily swap out a paneled wall section with piping. Another example would be what we like to call special situations. A special situation would be like if a mission required a sudden explosion to occur and an entire section gets blasted out into space. The way the new hall kits are made let us do cool new things like this a lot easier."
There's much more to the dev blog, and of course the revamp itself will be playable via the new Federation tutorial coming in Season 8.