SWU usage?
 

How long does it take DL to remove the SWU from your profile once used for an upgrade?

as soon as the ticket is re-issued.

what if it did not clear until at the gate?

thanks

if you get lucky 'never'. Depends on a lot of things. Intl. Y --> Z is usually different from domestic K --> G/Z.

thanks...i think might have been lucky. it has been over a week for a domestic upgrade and my coupon is still there

Happened to me long time ago 2x. Depends on the GA and if they have your redemption code, not just the cert code.

I've used them and they have not been updated.

I wish I could tell you that I've been able to double dip with one but I've never been able to use my allotment.

I think being able to use them is such a rare occurence that their system logic does not account for this.

I use all of mine and they have always shown as used in my account as soon as the ticket is reissued, which I usually ask be done early to allow time to fix any problems. Even the time this summer that I used a SWU strategically to get a gate upgrade into the last FC seat, the SWU was grabbed instantly by DL.

However, once during the merger I was using miles to upgrade TATL and noticed that the miles hadn't been deducted. I called because I didn't want to lose the upgrade or be prevented from flying that day. The supervisor who fixed it thanked me and remarked that she was amazed that the agent had been able to mess up my ticket so thoroughly as it shouldn't have been possible to reissue the ticket without taking the miles for the upgrade. She also confirmed that in all likelihood, I would have experienced severe problems at the airport if I hadn't called to point out the problem.

The bottom line is that you're probably home free on the gate upgrade you got, but anyone in the future who notices that SWUs were not taken when tickets were reissued with the upgrade should consider very carefully whether they want to point out the error to DL and the potential risks of not doing so.