GS1920-24HPv1 Firmware update via serial debug mode

Hello,

Recently I managed to brick my switch by uploading a v2 firmware. Now I have to somehow upload the correct firmware again via serial console cable connection.

Only problem is I am not able to find the correct firmware files. I found the EOL List, but this list only provides an archive containing a bix file.
https://webservice.zyxel.com/end-of-life
https://download.zyxel.com/GS1900-24HP/hotfix/GS1900-24HP_2.70(AAHM.3)C0.zip

Whereas every tutorial and manual I find talks about a .bin and a .rom file.
(e.g. https://support.zyxel.eu/hc/en-us/articles/360007264839-Why-does-the-Zyxel-Switch-cannot-boot-up-properly

Can anyone tell me how to either

• get a .bin and .rom file GS1920-24HPv1 or
• use this .bix file in cli mode?

Thanks in Advance,

Alex