You need to know your line of business and who else is doing the work you do, competing to be the team that's left standing to take it all.
Take, for example, Technology.
It's quite normal to have 3 teams are doing nearly identical work because they each support a/multiple different business unit(s). Maybe one team does more than the others, has a few additional job functions, and their workload is constantly increasing due to Agile forcing quarterly releases into monthly releases. Say on top of this, those groups lost half their EGS coverage, and couldn't backfill half their EGS FTE's who left right at the start of the pandemic but were vitally needed, took so long to get approved that one was short-staffed for multiple weeks, and rotated coverage to cover the EGS gaps. Say they also had typically been operating with 3 contractors since getting a single FTE was so difficult, especially for off-hours, but now they have none. That entire team is down roughly 60%.
That's before automation.
The next step is to think about how much of their job could easily be automated. Factor in that the main system of record for technology is being replaced with a new system of record that everything is going to run through. The new SOR also comes with predictive intelligence. AI that will learn what employees do and start taking over the simpler decisions and busywork.
Say that the group's day-to-day workload basically consists of telling development teams that their lazy and procrastinating selves didn't put the right information where they were supposed to. This is an epidemic because they just copy/paste and don’t update where they need to. the new SOR should fix this since there's no copy feature. Hopefully, the developers catch on. That’s only if they actually bother to fill it out before asking another team to accept that work and act on it. At this point, the team the devs are requesting work from is functioning as highly paid elementary school teachers that operate with students who can't always follow simple English instructions. If they can, some of them will still only do so after one or more verbal or textual confirmations. Consider that the new SOR is going to have access to everything they input and then cross-referencing it with how the data they provide to the other team to fix the issues, it's only a matter of time until it takes that job role over. Give it 6 months tops for that team's volume of work to drastically drop. The real question is how long it takes to impact the developer since it's recording that they’re terrible at version management and naming conventions, and spend a bunch of time fixing their own lazy errors?
Every time you use the new system, you're training the AI that's going to take over significant portions of your job role. Plan your survival timeline appropriately based on how complex and analytical your job role is and how long it would likely take a machine to learn how to do it well enough to function as a professional enterprise. I mean that as in, think of the average level of what passes for professionalism around here, and use that as the yardstick.
For the tech teams, the need will be shifted from manual multiple-choice test grading to automation production support by a remaining skeleton crew of 10-12 people. I already know a system that runs that way and I do not envy the people who work on it. They are lovely people, and they handle it with grace and professionalism, but it's obvious they have been gutted and shrunk to the skeleton crew and are getting dumped on with the increases in work volume the shift to Agile, as well as other enterprise initiatives have thrust upon them.
All three of the competing teams could be replaced with automation. One of the main reasons they exist is the separation of duties that an AI would provide. With that job role guarantee removed, that is 3 teams comprising of 39 employees and 6 managers (1US and 1EGS per team) which can be cut down to 2 teams consisting of 20 people. One domestic team consisting of 1 manager and 12 employees, one offshore consisting of 1 mgr and 8 employees.
That's a cool million saved right there. Rinse, repeat across multiple other BU's.
Cut the timeline number you come up with in half or a third and that's probably a good estimate of how long until all of that work goes away for you if you use SN. From the time SN is live, the clock is ticking.
There's your long, slow, cut over multiple years. Followed with a flourish.