Originally Posted by
Rescmajster
certainly the last day you get your luck depending on the eventual booking availability, but unless the biz class is fully fully booked or even overbooked, it would likely not an issue to enjoy the upgrade
I've been asked at the airport by TK if I was sure I didn't want to upgrade a same day flight using miles, so definitely not a difficult transaction for them.
Glad you were successful - and I as well