Japan 1st Jan holiday, all gas station closed.

Hi everyone, this is my first time posting here, I’m currently facing a really tricky situation in Hokkaido, and trying my luck here to find any help or solution, thanks in advance.

So here goes, I’m currently in Hokkaido, Furano, halfway through my 10 days road trip, I rented a car with Toyota-Rent-A-Car and had an appointment to return it by 10:30am tomorrow (1st of Jan) back in Sapporo, and here’s the problem, the car is currently running out of fuel and I’m hitting a wall trying to find a gas station that’s open near me, since it’s a public holiday in Japan, and I don’t think the fuel is enough to travel all the way back to Sapporo.

Here are some of my plan, and I hope someone can share their thoughts on whether they will work:

Plan A, the guesthouse owner told me that no gas station will open tomorrow in Furano, and that I should try head to Asahikawa to look for any stations that’s open, since it’s a bigger city compare to Furano, and nearer alternative compared to Sapporo, so I m planning to head to the 24h gas station there and hope they’re open next morning.

Plan B, in the event that the 24hour station is close, I would hv to return the car in Toyota-Rent-a-Car in Asahikawa, and take a train back Sapporo.

So yeah, sorry for the long read, I would be very much appreciate if anyone can share some thoughts and opinions on whether my plan would work, are 24hours gas station open during public holidays? or if anyone hv better alternative to suggest, thanks again if you made it this far, and sorry for my English.