If his levels keep rising, you have reason to be concerned. Read up on jaundice -- as I remember from when my son had it, the light (sunlight also) is to break down the bilirubin, and the liquid (breastmilk or formula) is to carry it out of the bloodstream. Both the biliblanket and lying in the sun work. (When my son had jaundice, it was winter, and we put him on a warm pad in a sunny window with the eye protectors on, and he lay there in just his diaper and got sunlight through the window, which was more light than a biliblanket provided. His bilirubin levels did go down, but he was also by then on both the breast and the bottle, so I can't tell you which helped more.) Your baby might indeed need the added liquids to flush his system that would be provided by supplementing with a bottle. It's not an argument against breast milk, it's about having a whole lotta lotta liquid go through him. If you are entirely adamant against formula, you might contact La Leche League and see if anyone in the area is producing extra breast milk and could share some with you right now, and you could feed it to your son in a bottle. You say he poops and pees like crazy, but how many diapers per day of liquids are you seeing? There is a number of poopy diapers and a number of pee-ey diapers they like to see a baby have, I think there are supposed to be at least 8 pee-ey diapers, and that's for a baby without jaundice. If the baby's bilirubin numbers don't start coming down, I wouldn't let a stand against formula prejudice me against doing what is needed to fight the jaundice. A baby can go on quite happily on breast plus bottle, but the consequences of jaundice (if it gets worse) are not good.
Oh, sorry, I see the part where you named the number of wet diapers. I read your post twice and missed it! My guess is that if his numbers are not beginning to come down, it might in fact not be enough liquid, even though it is enough for a normal baby to produce that many wet diapers. Maybe it just takes a little extra fluid when fighting jaundice. I'd also try the baby-in-sunshine thing instead of just the biliblanket.
Another possibility, and I would check this with your doctor for sure, is if you are feeding that much and getting a lot of milk, you could pump and measure the breast milk before bottle-feeding it to the baby. Once you have a baseline count and an amount, if the doctor or a lactation consultant says it is OK, maybe you could put some sterilized water into the bottle along with the breast milk, like 1/8th water and 7/8ths milk, to increase the amount of fluid slightly. This would only work if you kept pumping and producing as much milk as before, and if it worked, your son should have one more wet diaper in a day than he has now. (You don't want water to be a substitute for milk, just to sneak in a little more fluid into the baby's system. If the water starts to replace milk, forget the whole idea.) In any case, I would move fast. You don't want the situation to get worse.
My son also had jaundice at birth. As he was in NICU for the first 5 days of his life, they had him under a bili light. I too was breastfeeding at that point, but they did have to give him formula as well. Once he came home I was able to go exclusive breastmilk. I know you don't like the idea of formula, I didn't either, but as Annie said, the extra liquids can be very important in jaundice. I know you say he pees 8 to 9 times a day, and that's great as are the number of bowel movements. The rule of thumb though is 8 heavy wet diapers for a non jaundice baby and they want to see at least 10 with jaundice (at least that's what they told me). And again that's 10 really heavy wet diapers. Also, as Annie said, right now breast milk and formula are the best options for your child. I know they didn't want me to give him water. Anyway, I don't remember what my sons levels were, but they were high enough for them to be concerned. With the combo formula/breast milk they came down quite quickly. And he had no trouble at all going to 100% breast feeding afterward.
the doc old me to give him formula only for 48 hrs ...when his level was dropping.....i refused it and breastfed him and his levels dropped significantly.