LHR->JFK VS003 26/06

Hi - Looking for a tad of strategy advice.
I'm currently flying out on VS045 (K class) on the above date, but have found that ideally I need the earlier 003 flight. This is currently showing the following:
J9 D9 R9 Z0 S0 Y0 B0 L0 M0 Q0 X0 N0 O0
I have more than enough miles to upgrade to UC several times over, but there's no sign of a G or even Z seat there. I'll even throw some money in if that's what it takes, but last time I called CS they said flatly "no availability".
Any ideas welcome - but I guess the strategy at this point is probably ask at checkin?
Any better ideas welcome.
Cheers
I'm currently flying out on VS045 (K class) on the above date, but have found that ideally I need the earlier 003 flight. This is currently showing the following:
J9 D9 R9 Z0 S0 Y0 B0 L0 M0 Q0 X0 N0 O0
I have more than enough miles to upgrade to UC several times over, but there's no sign of a G or even Z seat there. I'll even throw some money in if that's what it takes, but last time I called CS they said flatly "no availability".
Any ideas welcome - but I guess the strategy at this point is probably ask at checkin?
Any better ideas welcome.
Cheers