So I a couple of really easy questions, but ones I need answered anyway.

1 - If I update a mod I've already uploaded to Workshop, such as changing a character's combat class or scripting, does it automatically update the Workshop when I save the newest version, or is there something else I need to do?

2 - (Relates to Q1) A friend and I are collaborating on some mods were working on. I'm mainly the designer, writer, shell creator (IE: I make the NPCs themselves, design the spaces) while he does the messy work (IE: Scripting, Triggers, Events etc.). For some of this, we'd like release the mod as a WIP and update it as we go - for example, we're fine with people using the follower with the basic follower functions and dialogue without any quests or custom dialogue for fun until we complete that follower's quest/dialogue etc. Since I'm the uploader and I'll only have the basic shell of the mod, when he completes the scripts/quests etc. what is the best way to A: Combine the two pieces without a ton of file-swapping? and B: Update the Workshop with the new version?

Thanks.

1) You have to upload to the WS again, ensuring the name of the plugin is the same. Make sure you repack your BSA.
2) WS is tied to one's steam account, so only one can upload there. If most of your work is in the plugin and theirs in scripts, I'd just trade files when needed and keep 'em synchronized so all is updated. Before releasing anything publicly, prepare a RC pack with everything up to date and have each member check that their work is intact.