You've hit the nail on the head to what I believe is the crux of the issue: OP is "jumping headfirst" into a cybersecurity role for a 30 person company with lar

You've hit the nail on the head to what I believe is the crux of the issue: OP is "jumping headfirst" into a cybersecurity role for a 30 person company with large/important clients without considering what they will need, beyond additional hard skills, to be successful. The background information is enormously helpful because, as you noted, it sounds like this is being thrust upon OP, but one can turn the conversation around and try to discuss what is actually needed to upgrade company security policies, infrastructure and processes -- starting with bandwidth (i.e. time). And carving out that time requires setting and managing expectations with both OP and CEO. Perhaps my wording came across incorrectly, but "interim CSO" doesn't mean vying for a title bump (although that's one power move OP could certainly attempt), but more to bring to the CEO's attention that this role is now important enough at the company's current size that it deserves full-time attention.