FlyerTalk Forums - Award Certificates Combinable?

Please post applicable links if they exist, but I have a couple q's about the award certs.

1) I assume as with the recent uppage on VS UC awards, we can ask for certificates before 03/16/04 and get the old mileage rate for the awards?

2) I am looking to bring a large(r) group on a trip (poor broke college students can't afford big trips, and I thought I'd help them out), and the options are within US (25k), Hawaii (30k), and Europe (50k). Since the only award that increases on 03/16/04 is the Hawaii award, I was thinking of cashing in for as many vouchers as I can for that award, and then if we decide to go somewhere else, just bring the vouchers with their 30k value and use them toward another award. Say I had 8 30k Hawaii Award Certs, and decided to go to Europe, I would like to turn in those 8 certs plus 10k from my account, and get 5 Europe awards. Is this a viable option?