Does anyone know if AmEx lets you balance transfer your current card?

I am going to balance transfer my current credit card to AmEx for a better interest rate, and I already have the card, however... they didn't give us enough credit for both our cards. If I balance transfer this one now, then in six months or a year or so, apply for a new card, will they let me balance transfer the AmEx I am about to get to a new AmEx to combine balances all into one card? I know this is confusing... sorry...