My ticket is Economy Light so I don't have any baggage allowance just the carry-on, so I agree I will pay for one bag ($70) at check-in.

My issue is what can I do if 72 hrs before the departure my bid is not approved? Can I still find a better seat available with more legroom?
When is the cut-off time when no changes are possible?

I am 6'4" tall long legs and need space for my knees
Thank you, guys!