Reprepro not mirroring everything

I have a reprepro 5.1.1 installation with the following conf. The idea is to mirror everything locally from Debian Stretch amd64 public mirror. "distributions": Origin: debian Codename: stretch Description: debian stretch mirror Architectures: amd64 Components: main contrib non-free Update: - debian-stretch Contents: .gz Log: /var/log/reprepro/debian/stretch.log SignWith: Origin: debian Codename: stretch-updates Description: debian stretch-updates mirror Architectures: amd64 Components: main contrib non-free Update: - debian-stretch-updates Contents: .gz Log: /var/log/reprepro/debian/stretch-updates.log SignWith: Origin: debian Codename: stretch-backports Description: debian stretch-backports mirror Architectures: amd64 Components: main contrib non-free Update: - debian-stretch-backports Contents: .gz Log: /var/log/reprepro/debian/stretch-backports.log SignWith: NotAutomatic: yes ButAutomaticUpgrades: yes "updates": Name: debian-stretch Method: http://ftp.us.debian.org/debian Architectures: amd64 Suite: stretch GetInRelease: no VerifyRelease: EF0F382A1A7B6500 Name: debian-stretch-updates Method: http://ftp.us.debian.org/debian Architectures: amd64 Suite: stretch-updates GetInRelease: no VerifyRelease: 7638D0442B90D010 Name: debian-stretch-backports Method: http://ftp.us.debian.org/debian Architectures: amd64 Suite: stretch-backports GetInRelease: no VerifyRelease: 7638D0442B90D010 The issue is that reprepro does not mirror everything that it finds in http://http.us.debian.org/debian/dists/stretch-backports/main/binary-all/Packages.gz . For example linux-headers-4.16.0-0.bpo.2-common is missing on my local mirror. But it has linux-headers-4.17*. This also goes for many other packages.