I called and talked with SWA right after they changed the points system because I wondered if the points would have expiration when they have been reserved, cancelled and put back into my account. They said that as long as my account is active, then the points are good.
We take friends and pay for their airfare. Since $$ travel funds are not changeable to another person any longer, we use points for their airfare, knowing if they cancel on us, we can redeposit the points and use them for someone else.