Forgot to deduct miles...
 

.....

well same thing happened to me, I called and asked for a one way BF upgrade from SJO to HKG (25k miles), they put me on confirmed F for SJO-EWR and the other one showed as waitlisted but no miles were deducted

I already considered the 25k miles MINE and then one day out of the blue (this is still about 6 weeks before the day of the flight) I see a new itinerary in my inbox........I knew it immediately :( , someone found out or a simple audit told them that there were short of miles somewhere .......and miles were deducted then (it took like a month for them to notice this)

so I would say, do not do a thing, they will find out on their own, remember to let us know what happens though

Now that it's posted here, you can be assured CO will quickly figure it out.

That's why I didn't say a thing here until now......when they fixed it, unfortunately even though I was quiet........CO figured it out :D

right now , CO Insider is going through all TATL milleage upgrades that were requested for both legs......looking for the tiny 20k miles missing somewhere

Heed wolfie's cautionary tale by frequently taking reward tickets to keep your balance low. What are they gonna do? Give you a negative balance?

I still can't figure out why people are trying to get the upgrade without the miles. After all, the upgrade is already a reward for the miles. Isn't it a bit unethical to try to get away with not even using miles?

People are not trying to upgrade without the miles, I for one, simply do not need to be catching up with other people mistakes or omissions. Long long ago I stopped being 'quality control' for hotels/airlines/car rentals/etc, its their duty not mine to charge me, if they catch it great, they are suposed to, if not it simply balances it out with the other times when a mistake oh their end greatly inconvenienced me, cost me extra money or downright tried to screw me. (and I am not talking about Continental at all, simply the 'big picture' where a hotel here and there manages to screw a trip for x/y/z reason or a bag has a missing item or......etc)

It is (or was) very well possible to have a negative balance.