In a Debian-style APT repository, the pool/ directory groups packages primarily by source package name and binary package name, version, architecture, etc. If two distinct .deb files have identical name and version (as seen in their control file) and same architecture, reprepro will report a conflict when adding one after the other. So, we need to append distro-specific string to the existing version in order to avoid such conflict when creating VeraCrypt APT repository.