's post "Get Custom Answers Using ChatGPT’s Memories, Projects, Custom Instructions, and GPTs" in the AI Amplifier club, he goes into detail and workarounds for, "Unfortunately, Projects don’t automatically reference other chats within the same Project. Each chat is separate. If you want a Project to remember information across conversations, you’ll need to save it to Memory or upload it as Knowledge"
That' hasn't been true since April. I know it takes significant time to put together these things and it will probably never keep up with the pace of change, but this is one section I think should be updated.