Sysops are automatically granted the ipblock-exempt right. As such, they shouldn't be affected by IP blocks, but that turns out to be false.
Steps to reproduce:
- Block an account indefinitely with autoblock enabled
- Sign in with that account and then logout
- Go back to your account with sysop access
You'll find yourself autoblocked and unable to take any action due to the removal of the unblock-self right.
From the merged-in task
It appears that admins are affected by IP autoblocks, despite having IP block exemption.
18:31: I block my test account (User:WK-test) on enwiki with autoblock disabled for 10 minutes.
18:32: I log out of my admin account (User:Writ Keeper) to log into my test account and make a test edit to User talk:WK-test. It completes successfully. I then log out of my test account and back into my main account and verify that I can still edit pages.
18:34: I change the block settings on WK-test to enable autoblock, and nothing else.
18:35: Again, I log out of Writ Keeper and into WK-test and make a test edit to User talk:WK-test. I log out and back into Writ Keeper, and the Writ Keeper account is now affected by the autoblock, despite being an admin, which should imply exemption from autoblocks.
Screenshot of the message shown (note the time--18:40, while the 18:31 block is still active--and that the logged-in user is Writ Keeper): https://commons.wikimedia.org/wiki/File:AdminAutoblock.png