My car submerged in the water last week due to the heavy raining that caused flooding in the underground parking. The car was parking on a gradient therefore only the rear right side of the car was submerged. I was able to open the doors and start the car without any issue as the water was not that high. The rear back flooring was wet. The damage had been assessed and the estimate for repair is £800 (carpet change and checks). However, my insurance company called me saying that it has to be written off as total loss Cat B. I am sure that the insurer only decided to put it in Cat B because they heard the word "submerged". Now, I would like to appeal the category and put it in cat C or if I cannot do that, I would like to keep the car and put it back to road even if it is Cat B. There is literally no money has to be spent on it except for the DVA checks it may need. I know the insurer guidelines and the car has to be destroyed but I heard that it is possible to put back on the road I was wondering what are my options?