Excuse the metaphor. I'm in the same boat, I have CNG and I am holding out as long as I can. I love the way it cooks (and bakes). Hate the weight of the tank and the lack of sources to fill it. I have one source in the SF Bay Area and at $38.50 a pop.
I bought a back-up un-pressurized alcohol stove top (Oringo) that I will use when the stove stops working or my source for gas disappears. I have used this type of stove on other boats and they are ok. They are difficult to find now but work so simply they are unlikely to break down. If you can find a used one, the cost is a fraction of what it would cost for propane. Mine came from a Catalina 22. It was unused and $300. I am told I overpaid but felt that I could afford it at the time. I will loose the ability to bake cookies and frozen lasagna on long races as it does not have an oven. That sucks but can make due with hot ramen, coffee, tea and canned chili! Nothing like canned meats!