Do I have to upgrade to 2.4.9 immediately?

You don’t have to upgrade to 2.4.9 the day it ships, but you do need to be on a supported, patched line. If you’re on 2.4.4 or older, your version goes EOL in 2026 and stops receiving security patches — that’s the urgent case. For 2.4.5+, you can stay on your current line as long as you apply the May 12 security patch (2.4.x-pYY).