So I was kind of thinking about this today. As far as installing a9lh we have to downgrade our system all the way to 2.1 to get to a system that has access to extract the OTP. However what my question is is can Nintendo create a signed update that unlocks access to the OTP to retrieve the files to then remove a9lh from systems? Is it setup so that Nintendo themselves would also have to force downgrade user systems to be able to uninstall a9lh? (Which is something very very unlikely that they would do since it wouldn't make much sense to do it). If this is the case that they can't create such an update to remove it without the full downgrade I guess a9lh is really pretty full proof since it would be so hard for them to remove from user systems.