If you have 17K due, I'm guessing a large portion of that is for housing. First, you can defer payment, so instead of having one large ~$13K payment for the dorm, you can break that up into ~$1.5k per month. You can do that via e-bill.
And yes, there is a 30 day grace period where you won't have any late fees. So while the bill is technically due Aug 15th, there is absolutely no penalty if you pay it later than that (up to 30 days). After that I think it's like a $20 late fee. So my advice to you (and everyone) is to not pay the bill until you see all your loans/grants paid thru. Last time I checked, on Bearfacts it says they have been processed but it's still not reflected on the actual CARS E-bill. So wait until then. If you do pay now, once your loans/grants get processed you will get a refund for the difference.
If you have private scholarships (i.e. not Berkeley's Regents), some of them may take some time to be sent to Berkeley and be processed so you may have to pay some of the bill, and again you'll get reimbursed (or credited) once that scholarship is received.