My group is currently running on a 1-1 game day to real day system partially for stronghold management and partially cause I had designs of a west marches lite system but after a month of running it like this I think we're gonna switch to a more reasonable system of time skips and "fellowship phases" to steal from The One Ring 2e. This will make gameplay better probably but will be a pain in the ass for stronghold management and keeping synced time scales between the parties. As it stands, the plan is to update the stronghold every in game Sunday rolling stronghold events, updating the stockpile with stuff from the hirelings, and making any payments. Some of my PCs are very invested in the stronghold and others aren't as much so I'm not sure how to balance this.
On top of this, I'm splitting my party. Currently my table is 7 players and due to it being a lot for me to manage, some players feeling left behind in a large group, and sessions running a bit too long I've decided to put a 4 players per session cap on it all with the game running week to week. Week 1 is Party A, Week 2 is Party B and back and forth so on and so forth. These parties will each have a PC for a player so they can dive right in to either party if they want but whichever PCs aren't being played that session will be narratively off screen camping or keeping safe in a town. This allows for them to focus on multiple tasks and get more done as well as give players a week break from playing if they need it. Upon thinking about it though, I'm unsure how to manage the timeline for these two groups without the 1-1 game time real time system. I was thinking since I'll be pulling in the fellowship phase as a reference, we keep it to 1 adventure per party per "month". Maybe in Fallwane 1165 one party is exploring the Vale of the Dead while another party is off treating with Zertorme in Amber's Peak, then in Winterrise 1165 Party A is down in Haggler's House dealing with that while Party B is delving into a dungeon. Gameplay goes as such and once they are done their requisite adventure for the "month" they enter into a downtime fellowship type phase for the remainder and can chase their goals. My player seem to enjoy that stuff (and I'm sure some people he wouldn't) so I don't see a lot of issue with this. Everything still works on mostly weekly scale allowing for me to manage the stronghold and roll faction actions behind the scenes but one group shouldn't ever be overlapping the other group time wise.