Here is a workaround I posted as a solution to another GPT problem: I have created custom GPT (my GPT) on GPT-4. How so I run in on GPT 3.5 turbo? - #12 by SomebodySysop
To be clear, this is a solution that requires a developer, and only makes the slightest bit of sense if you intend to offer your solution outside of GPTs (ours was created before GPTs, and we had no intention of using GPTs at all until we saw this post: You can access Mistral API via Custom GPT action)
And, if course, it will come with it’s own challenges. But I’ve implemented this, and it works.
GPT <------ API Action ------> RAG Knowledge Base
Now you have complete control over how the knowledge base is embedded and searched. And you can still put it in the GPT store!