AFAICT as soon it is in Debian testing (which currently has 0.148.1, only Debian unstable has 0.148.2) it will land in Kali.

s390x systems were initially inoperable

Kali doesn't support the s390x architecture, so I don't understand why this bug report. Can you clarify?

Apart from that, indeed Kali is based on Debian testing, so when initramfs-tools 0.148.2 enters Debian testing, it will be in kali-dev as well, then in kali-rolling a few days after.

This report has been filed against an old version of Kali. We will be closing this ticket due to inactivity.

Please could you see if you are able to replicate this issue with the latest version of Kali Linux (https://www.kali.org/get-kali/)?

If you are still facing the same problem, feel free to re-open the ticket. If you choose to do this, could you provide more information to the issue you are facing, and also give information about your setup?
For more information, please read: https://www.kali.org/docs/community/submitting-issues-kali-bug-tracker/