Advice on transitioning a current membership offering into a new upgraded offering?

I run my business as an artist teaching art online. I’ve been offering a monthly membership program for 3 years at $39.95 and they get a set number of art lessons. This was my very first offer and it’s been successful. Right now I have 450 paying members in this program.

However, that current offer limits me on what I can help my students with. So the last 2 years I’ve been creating additional courses, masterclasses, mentorship etc that helps them with art business, finding their artistic voice, in addition to more technical training. I’ve been selling these a la carte for $200-$1000 each. Many of my current members have bought them.

My vision is to stop selling these a la carte and have them included in a NEW membership package instead. I want to have 1 membership selling at $100 a month and 1,000 members for $1,000,000 annual revenue.

My goal this year is to produce 2 new courses/classes each month to put into this NEW membership school to make it a Mercedes selling for $1!

I have no problem creating valuable content. BUT of course, I have no idea how to transition my current customers into this new offering. Many of them have already bought these courses I’ve already made…so the new product won’t be of value to all of them. If I’m making the new classes, courses to add to the school to boost its value when I launch this….I don’t know if I should hold onto the content and not sell it until I’m ready to do so? Or do I just keep selling a la carte until I’m ready to launch. Do I launch the NEW membership, while keeping the old membership alive (but stop enrolling for it) for a certain period of time ….so that I don’t lose too many paying customers in the transition?

I really admire the 2 offer system that Brooke has created and I long to simplify my offerings while helping my customers on a deeper more fulfilling level. Thank you so much in advance for any advice you can offer me!