Package installation unreliable on systems without RTC

It seems that when you specify "packages:" to be installed in the cloud-init user-data, it attempts to update the repository files and install the packages straight away, without waiting for date/time to be synchronized through NTP.
This creates problems for systems without RTC (like the Raspberry Pi) that do not have valid date/time at that point yet, as apt throws a fit if the InRelease files are newer than current time.

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Cloud-init v. 21.3-1-g6803368d-0ubuntu3 running 'modules:final' at Wed, 13 Oct 2021 13:33:26 +0000. Up 47.18 seconds.
Get:1 http://ports.ubuntu.com/ubuntu-ports impish InRelease [270 kB]
Get:2 http://ports.ubuntu.com/ubuntu-ports impish-updates InRelease [110 kB]
Get:3 http://ports.ubuntu.com/ubuntu-ports impish-backports InRelease [101 kB]
Get:4 http://ports.ubuntu.com/ubuntu-ports impish-security InRelease [110 kB]
Reading package lists...
E: Release file for http://ports.ubuntu.com/ubuntu-ports/dists/impish/InRelease is not valid yet (invalid for another 1d 3h 1min 32s). Updates for this repository will not be applied.
E: Release file for http://ports.ubuntu.com/ubuntu-ports/dists/impish-updates/InRelease is not valid yet (invalid for another 37d 3h 47min 18s). Updates for this repository will not be applied.
E: Release file for http://ports.ubuntu.com/ubuntu-ports/dists/impish-backports/InRelease is not valid yet (invalid for another 37d 3h 47min 29s). Updates for this repository will not be applied.
E: Release file for http://ports.ubuntu.com/ubuntu-ports/dists/impish-security/InRelease is not valid yet (invalid for another 37d 3h 47min 13s). Updates for this repository will not be applied.
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Think you should wait until systemd reaches time-sync.target before doing anything through apt.