The best thing I can suggest to really tell if it's open is to watch the PKI Webcam for a little while and see if you spot any trains. As for this weekend, I wouldn't be too hopeful. I've been watching the web-cam this morning, and I do see trains running on King Cobra, Adventure Express and I think I saw one on Top Gun. But nothing on the big SoB... Don't see anyone going into - or coming out of - the station. (Whichever side faces the webcam) It's 11:42 here, which means it's about 2:42pm. there.
*Sigh* Oh well, as long as it's open the week of June 12th. We'll be hitting CP & PKI somewhere around June 12th (my b-day) to the 14th.