Sounds like the yardage is in two pieces, the 8 yard bolt and another piece. If I was looking at this I would begin by prewashing the other piece after carefully measuring WOF and its length. That would tell me how much shrinkage to expect and how to proceed. If the other piece is not the same as the bolt fabric then I would wash the bolt fabric in my deep sink. You don't need the usual amount of laundry detergent, just a tiny amount, enough to remove the fillers. Use water that is as hot as would be used for future washes after the quilts are done. Some people only wash with cold water, for instance. The beauty of a deep sink is the fabric is only agitated by you, then the plug is pulled to drain, and refilled to rinse, etc.,etc. To dry, I have a garment rack from Walmart that I use. I take about three or four hangers and thread the yardage through, letting the fabric drape down between hangers. It's a pain, I have to fold the wet fabric over lengthwise twice, but I've done it enough that it just is what it is. Part of the process. Then I put old towels down and let it drip dry awhile. Since I always prewash I'm usually taking my fabric to the iron once it is "just damp". Another trick is wrapping the damp fabric in plastic wrap and chilling it in the fridge before ironing. This works with fabrics that want to crease.
The only thing not addressed here is what happens with drying in the dryer and how that affects shrinkage. With my old school approach to life, I guess I would let the fabric drip dry as far as needed to approximate what things look like coming out of the washer, then chuck it in the dryer and hope to heck it doesn't tie itself in knots.