https://commons.wikimedia.org/wiki/Category:ACC_needing_decomposition should have hundreds of entries due to https://commons.wikimedia.org/w/index.php?title=Template:ACClicense&diff=97981200&oldid=96992960
However that didn't seem to happen. I tried making an additional edit just to make sure, still nothing.
Originally reported at: https://commons.wikimedia.org/wiki/Commons:VP#Bug_report_-_category_modification ( https://commons.wikimedia.org/w/index.php?title=Commons:Village_pump&oldid=98809679#Bug_report_-_category_modification )
(I did tests of templates with only one back link and it worked fine)