When trying to locally unblock 2001:41D0:0:0:0:0:0:0/40 (globally blocked) at pl.wp (https://pl.wikipedia.org/wiki/Specjalna:Lokalny_status_globalnych_blokad) I get the following error:
Your change to the local status of a global block was unsuccessful, for the following reason:
You made no change to the local status of this block. Return to the global block list.
I can confirm the block by unchecking the checkbox – this works, but when trying to unblock again I get the same message. The block itself is not being lifted, of course.