We've been on an annual budget plan for years where they bill you a fixed amount each month, and then we ante-up any overage in July and they issue an adjusted rate for the next year based on current cost. My monthly was $182/mo. but now it's $454/mo. effective July. Our boiler uses oil for both hot water and baseboard heat, and it's not like we can just rip it out and replace it with all-electric stuff without a huge outlay.
I'm really torqued over this. If you're a heating oil consumer, prepare yourself to take it in the rear.
If you can buy the propane tank and get someone to install it, it will put you in the drivers seat instead of being held hostage to on or the other. If the propane co does the install, you are theirs until the end of time.