“I am moving from IT into IR, what’s the route”
Every step opens something already published on this site. Skip what you already know; the order matters more than the completeness.
Start with the map. IR reuses most of what you know; this shows where it fits.
The classic bridge document for people with systems skills. Short, practical, and speaks fluent sysadmin.
The two playbooks closest to your existing instincts. You already know the systems; these add the response discipline.
The Runbook where IT administration maps most directly to response. If you have run a mail tenancy, you are halfway there.
What an IR programme looks like on paper. Read both from the document library, then compare with what your current employer has.
The habit that separates IR professionals from firefighters. Also the best interview answer you will ever give.
The tooling and reference material practitioners actually use. Pick two tools and learn them properly rather than ten superficially.
A mentor who made the same move is worth more than any course. Ask for one.