When to call ScrollTo on a WebView

Question

I want to open a website in a WebView and then have it start a certain pixel distance down the page.

I see the WebView has a scrollTo() method, but when is the soonest I can call this and how do I detect that?

I would like to have it appear to the user, that the page opens up at the scroll position. So I don't want to wait until the entire page is loaded. If it did wait, then the user may have already started scrolling and once it loaded, the scrollTo() would appear to grab control from them.

Thanks