First, post your current automation.
There are a few ways to approach this… so we need more information.
Is the “B-12” calendar event an “all-day” event or does it have a specific start time? If it’s not all-day, is the start always at the same time? If either of these are true, it should be possible to use a Calendar trigger with an offset so it fires at 6am.
If the “6am” automation runs should the “7am” automation still run as well?
Just FYI, ChatGPT and the other bullshit engines are bad at Home Assistant and produce a lot of plausible-looking, non-functional configurations. HA updates frequently and the majority of available examples that LLMs can pull from are old and/or from people posting non-working configs here or on Reddit. Deciphering and correcting LLM slop often requires a higher level of knowledge than it would take to just create the config yourself from scratch.