Just got 6 Platinum upgrade certificates for 2010. My wife and I talked about ways to use them and eventually settled on a trip to JNB. I've never been there, and I figure it would give me a chance to check out the suite seats in BE on the 777-200LR on the ATL-JNB leg.

I called the elite line w/credit card in hand and despite near complete flexibility on dates, the rep couldn't find any upgrade availability. She checked over 20 dates - some of which had no confirmed BusinessElite bookings - and nada.

Does anyone know if Delta even allows upgrades with miles or certs on this route? Is there any way for me to search myself using the web site?

Seems odd as I was ready to drop near $8K on two upgradeable coach tickets only to be stymied. If someone walks into my business with that kind of cash in hand, I would find a way to complete the transaction...

Ken