Strange Debian package renaming

Running PKGget, I installed Midnight Commander; however, although it did install, the list of installed files is supposed to be in /root/.packages/filesdb/mc*.files, but the file doesn't even get created.

I traced the reason to lines starting at 398 in /usr/local/petget/installpreview.sh; it reads /tmp/petget_missing_dbentries-DEVUAN which has this:

mc-data_4.8.33-1|mc-data|4.8.33-1||Filesystem;filemanager|6277K|pool/DEBIAN/main/m/mc|mc-data_4.8.33-1+deb13u1_all.deb||Midnight Commander - a powerful file manager -- data files|devuan|excalibur|cecd52dc25bc836f156cbd0355b7bdb7||
mc_4.8.33-1|mc|4.8.33-1||Filesystem;filemanager|1590K|pool/DEBIAN/main/m/mc|mc_4.8.33-1+deb13u1_amd64.deb|+libc6&ge2.38,+libext2fs2t64&ge1.37,+libglib2.0-0t64&ge2.78.0,+libgpm2&ge1.20.7,+libslang2&ge2.2.4,+libssh2-1t64&ge1.2.8,+mc-data&eq4.8.33-1|Midnight Commander - a powerful file manager|devuan|excalibur|4dd43eeaaab3528527bf74fa35821243||

The script then looks for existence of a package named "mc-data_4.8.33-1*.deb" (glob wildcard) in /var/cache/apt/archives/ but it doesn't exist. The installed package is supposed to be there, and it is, but is named "mc-data_3%3a4.8.33-1+deb13u1_all.deb" ...hmmm.

I checked online at https://packages.debian.org/trixie/all/mc-data/download, the package is named "mc-data_4.8.33-1+deb13u1_all.deb", so why has apt changed the name in the archives folder?

I cannot find an explanation for this, so have put a hack into 'installpreview.sh' script.
If it cannot find "mc-data_4.8.33-1*.deb" then falls back to looking for "mc-data_*.deb"

Ah, figured it out. See this:

# apt info mc-data
 Package: mc-data
 Version: 3:4.8.33-1+deb13u1
 ...

"3:" is the "epoch" number. apt has renamed the downloaded .deb with the epoch number, but has actually renamed "3:" to "3%3a". OK, but confusing.  

Tags: easy