Therein lies the key. Getting as much of the present network bedded in and established so that it can grow when the USPBC arrives...
I'm not convinced AA and UA will have the patience to wait that long - they're all about maximizing short term profits and shareholder returns / management bonuses. And they both have large networks to re-deploy assets into when a particular market goes pear shaped for them.
In the UK regions they are both facing the double whammy of an uncertain UK outbound market for next year due to the weaker pound etc, and better quality offerings from the competition. The next few months will be interesting