Thank you all very much for your replies and suggestions. 777, you mentioned some way to protect UA miles through diners club. could you elaborate on details on doing that. I have a diners account. Several of you suggested participating in star through LH instead of UA. I tried to study LH's rules on their website but found them a little hard to understand, especially given the layout. However, it is my impression that LH's plan is not as favorable as UA's, even though they are both in Star. Is that a fair conclusion. If so, then it looks like it would be a trade-off between more favorable rewards with UA versus more security of banked miles with LH.