I bought an upgradeable DEN-BKK intl economy ticket. The first and last legs are short domestic flights, and those upgrades cleared. The international leg upgrades are still waitlisted, and I am now 3-1/2 days from departure.

It would be a shame to waste SWUs on the outgoing DEN-LAX and return SFO-DEN legs alone. However, when I do a first leg, I may not yet know whether any intl segment upgrades will clear.

If none of the intl upgrades clear, will UAL (on request) restore my SWUs and charge me some 500 milers for the short-haul domestic legs?