First Class on points
 

struggling to find much award availability in december. Curious if im more likely to be able to book/use points for J and then miles to upgrad inside 72 hours than I am to find F availability. Does that seem likely? Or just keep searching and hope something opens up as I get closer to flights? Which method has been more successful for people here?

Where from and to?

Trying to get back from the maldives. Good to get business class on miles and then try to use points to upgrade as we get closer. Any idea if there is generally better availability to do this on the a380 flights to JFK or Houston? Dont want to risk getting stuck on 777 business class to chicago, so would rather just fly into one of those spots and then get a different flight once clearing customs in the US.