I could probably work around this by uninstalling coreutils-tail prior to the upgrade and reinstalling it afterwards. However, I think this is something the updater should handle.
I had similar issue with vsftpd(with ssl) vs vsftpd(without ssl) some time ago. So i made entry for uninstalling conflicting package in “user.lua” file /etc/updater/conf.d/user.lua --> Uninstall ("vsftpd",{priority = 60}).