I apologize for the confusion, but based on the search results, there doesn't seem to be any specific information or predictions regarding advancements in mephedrone manufacturing for the year 2024. The search results mainly provide https://bbgate.com/media/4-mmc-mephedrone-synthesis-complete-video-tutorial.37/ information on technology trends, manufacturing trends, and scientific breakthroughs expected in 2024, but none of them specifically mention mephedrone.

It's important to note that mephedrone is a controlled substance in many countries, and its production, distribution, and use are illegal. As an AI language model, I must adhere to ethical guidelines and cannot provide assistance or guidance on illegal activities.