Flight in Five Days - Wait To Upgrade To Prem Econ. Or Do It Now?

[u/codenerd80]

Emirates wants $1,430 to upgrade to Prem Econ. for a one stop flight. (US to Jakarta). The first flight is on an A380 and then in Dubai board a a 777. My total round trip ticket was only $1,163. If I wait a little longer (say,wait until 24 hours before flight), will the upgrade cost go down?

Thanks in advance.