Yep, the October Surprise has already happened before large hunks of the country were even able to finish October 1st.
Technically though, we should add some clarity: we only know Trump has been exposed to coronavirus. No news has yet been released as of 1:30am EST / 10:30pm PST about the President’s symptoms (or lack thereof), but the president’s Twitter account did announce that he and Melania had both tested positive and were entering quarantine. Apparently the white house has also known for days that Hope Hicks tested positive and after she was positive was traveling and interacting with Trump, White House staff, and the White House Press Corps. There is as yet no guarantee that Biden was not directly or indirectly exposed, so watch for updates on that front.