How does IS&S compare, relative to other orgs at the company? Does the org you work for (in contrast to your role or seniority level) matter, when it comes to job security?
IS&S is much more stable than IS&T, but you'll likely get light, unofficial disdain from software engineering because the organization has a reputation of working on some of the poorer-quality products at the moment. I have heard from the grapevine that Apple is hiring aggressively at the moment, and I wouldn't expect a layoff given that they're huge and fairly financially secure. Large corporations usually weather recessions fairly well. But I have no firsthand experience with your particular situation and I'm just a random person on the internet, so YMMV.