The cutoff for paying your deposit is 11:59pm tomorrow. I would not wait until that time. If something goes awry, there will be no one to help you and the gateway will close. Please try and log onto SIS earlier in the day.
Please also keep in the mind that simply clicking the "accept" button does not save a place for you in the Fall. Hitting that button puts you in an "intends to matriculate" limbo. Only when you pay your deposit through UVaQuickPay (aka NelNet) will you become matriculated.