Your bug report

#18551: regression: erc-format-nick is now essentially an alias to erc-format-@nick

which was filed against the emacs package, has been closed.

The explanation is attached below, along with your original report.
If you require more details, please reply to 18551@debbugs.gnu.org.

-- 
18551: http://debbugs.gnu.org/cgi/bugreport.cgi?bug=18551
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