RFE: please have rpmdev-bumpspec populate the changelog date using local time, or if it is using UTC specifically for some reason, add an option to use local time. I find myself always having to edit the date manually because it's usually the next day in UTC when I run it. :-)
It is specifically using UTC because rpmbuild parses the date as UTC. For that reason I don't think adding an option to use anything else would be a good idea.