Sorry, but I don't think you understand it right. As long as it stays "Current", everyone who has submitted their documents and were approved, will get an interview appointment. I didn't say that everyone who has and WILL submit. Obviously there isn't room for all the 100k selectees as there are only 50k visas. I'm just saying, if at anytime you did submit your docs and they were alright, if your region becomes Current, you will get an interview call up.
Once visas are up, status will change from Current to UNAVAILABLE, therefore no more visas are available and anyone wishing to submit their documents at this later stage can no longer receive an interview appointment. Hence the "Based on visa availability" in my previous post.
Cheers