I have no idea what will happen on the open, but don't flip out when SLV gaps down. And whatever don't trade in the first 15 minutes of market action. There is to big a risk of getting whipsawed.
Notice that in the overnight chart of silver the bleeding seems to have been abated a bit. The price dipped below $45, but now has come back by about a dollar. That is what we want, people buying dips. The SLV will whip around, but keep in mind that the underlying physical id holding up here.