runAfterUpdate not working

Hello,
Can someone please tell me what i am doing wrong here.
I try to run the runAfterUpdate script in de utils directory using the container console of portainer. I am using the Raspbian stretch edition.

sudo ./runAfterUpdate.sh
Cleaning up BrewPi script directory…

***** Installing/updating required packages… *****

Reading package lists… Done
Building dependency tree
Reading state information… Done
Package php5 is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

Package php5-cli is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

Package libapache2-mod-php5 is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

Package php5-common is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

Package php5-cgi is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package ‘libapache2-mod-php5’ has no installation candidate
E: Package ‘php5-cli’ has no installation candidate
E: Package ‘php5-common’ has no installation candidate
E: Package ‘php5-cgi’ has no installation candidate
E: Package ‘php5’ has no installation candidate

*** ERROR ERROR ERROR ERROR ERROR ***

See above lines for error message
Script NOT completed

***** Updating cron for the brewpi user… *****

sudo: crontab: command not found
Checking entry for brewpi …
Done checking entry brewpi …
Checking entry for wifichecker …
Done checking entry wifichecker …
Restarting cron
sudo: /etc/init.d/cron: command not found

*** ERROR ERROR ERROR ERROR ERROR ***

See above lines for error message
Script NOT completed

***** Fixing file permissions for /var/www *****

***** Fixing file permissions for /home/brewpi *****

I see the script is outdated.
You should not be using it with docker.

To update to the latest version, just re-create the BrewPi container.

In portainer, you have a button to recreate the container. Leave ‘pull latest image’ checked.

Can I conclude that the only relevant scripts when using docker are:
flashDfu.py and updateFirmware.py?

Yes, and I will update those too when I release new firmware.
Only the firmware updates will be done by running scripts in the container. For all other updates, you just pull the latest container.