PSA for anyone who wants to jailbreak and has a brand new kindle

It appear that amazons new production line release 5.8.9.0.1, which is shipping on many devices can be jalibroken without downgrading. This version apparently ships with the development files that the recovered factory images had. You can start at step 1 on mobileread.
Additionally, anyone who has a brand new kindle with another version, should be able to downgrade to the factory versions listed in this thread . The downgrade protections do not seem to apply until your device does at least 1 update - over wifi or USB. So make sure you stay in airplane mode, or skip wifi on bootup.
( DO NOT USE DOWNGRADE ON PW3 32gb manga model - you will brick your kindle if you install 5.7.4, though I have a test package I am looking for volunteers for, that may or may not brick your kindle. )