Yeah I got an early upgrade to WP last year only 2 1/2 months after I hit SG (early Sept) for the first time. It was during the double SC offer that lasted ages and the cheapo Business fares between ROK -BNE - ($199 each way IIRC). I had a heap of mini trips planned which moved me up pretty fast and I worked out that I would hit WP of my own accord by some flights I had booked in April this year.
Then in Nov last year I was surprised with an early upgrade to WP even when I had over 200SC to go. I definitely had the sectors down though - well over. I was worried I wouldn't maintain WP by Nov this year as I've taken less flights and that double SC offer ended 30 June and none since. But I've just hit it again with a visit to see my son 16-18 Nov - flight back pushed me over. While the early upgrade is nice I understand both sides of it - especially when you've planned things down to a T to get the upgrade when you wanted it.