I don't know if it's of any interest, but in Australia, the soaps are written in a very similar way.
The department normally consists of the following in this order of hierarchy:
Script Producer - has overall control over the story and script
Associate Script Producers - one oversees story room, one oversees scripting
Storyliners - two or three in the story room with the Associate Script Producer
Script Editors - two or three, rotating weekly, overseen by Associate Script Producer
Script Coordinators - the cogs that keep the admin turning
Every few months, the team have a story conference with the Series Producer who oversees the day-to-day production. They're on the same "level" as the Script Producer. In that story conference, the overall arcs are discussed, working with the stories that the Script Producer wants to tell.
On a week to week basis, the following happens:
Week starts with a fleshing out of the stories and what/who will appear in what episodes (only so many sets/locations allowed per week, and cast are contracted to 2 or 3 eps a week);
The story team then plots the episodes scene by scene into 'plot notes', which are sent to freelance writers. This process tends to use coloured post-it notes to identify the stories and the process can take up to 2 days. Process normally involves running all the 'story beats' (ie. the scenes) and then weaving them to get the best flowing episode. This process can also see short-run stories conceived by that team - the script producer normally delegates this process to their associate and the storyliners;
When the writers come in for their meetings, they are briefed scene by scene and then go away and write a 'scene breakdown' (SBD) which is a 10 page document, that puts into prose what will happen in the episode, using the plot notes that have been plotted by the in-house team;
Once the SBD comes in, the Associate and the Script Producer both edit it, before it goes back to the writers to write their scripts. They have two weeks to write the scripts. The 'block' (the 5 episodes for the week) are then edited by a script editor and 'over-edited' by the Associate and Script Producer, before being released to production through the Script Coordinator.
Overall, seems like a similar process to the US model, but the 'breakdowns' (scene by scene) are actually written by the freelance writers themselves and edited by the 'head writer' (our Script Producer).
Edit: The Script Producer normally has meetings with the Head of Drama/Network Script Executive where their long-reach story arcs are approved or denied. They all get to read/comment on the SBDs. However, my understanding is that it never normally reaches a network level when it's been scripted.