How to apt upgrade including deferred updates due to phasing

When you run apt upgrade you might see a message like this:

# apt dist-upgrade -y
Paketlisten werden gelesen… Fertig
Abhängigkeitsbaum wird aufgebaut… Fertig
Statusinformationen werden eingelesen… Fertig
Paketaktualisierung (Upgrade) wird berechnet… Fertig
The following upgrades have been deferred due to phasing:
  acl krb5-locales krb5-multidev libacl1 libboost-atomic1.83-dev libboost-atomic1.83.0 libboost-chrono1.83-dev libboost-chrono1.83.0t64 libboost-container1.83-dev libboost-container1.83.0 [...]

This means that some packages are not upgraded at the moment, because they are part of a phased rollout. This is done to prevent all systems from breaking at once, in case a bad update is released.

To force upgrading all packages, you can use the following command:

apt -o APT::Get::Always-Include-Phased-Updates=true upgrade