I just bought a Galaxy S10E recently to fuck w/ LineageOS and possibly boot iOS on it because I'm insane. It arrived today, so I unbox it, set the thing up, and check about phone. Turns out it's running OneUI1 with a security patch from like oct2019.
This isn't the 1st time I've gotten an Android device from a non techi person which ran essentially it's rtm build. Update your devices people. At the very least you'll save people like me from now having to sequencially install like 1000 updates, and at most you'll actually protect your self from malware and other nasty things