They won't let me change my IAH-AUS-IAH-LGW routing for later this afternoon; with a very possible WX bump as a result of the AUS-IAH leg getting delayed most likely (the weather is not getting any better here, and they seem to have no other option they are willing to offer - other than deleting that stopover, or delaying the LGW segment). And because its a intl trip that ends after the 20th, the WX exception does not apply. Wish me luck...