in your case, the visa was about to expire in Aug 12, but the authorities allowed you to renew it in May ,right ?

the earlier case-- the wife already left Qatar ( for example Feb 12 ) , but still holding the visa. As per the rules, she had to return wtihin 6 months ( Aug 12 ) and she cannot come back. Here there is way, by paying QR 500, the authorities give a waiver to the rule of Aug 12 - instead of 6 months , they give 12 months. Means, she can return only within Feb 13.

BUT KEEP IN MIND -- HER ACTUAL VISA DOES NOT GET EXPIRE DURING THIS 12 MONTHS. IF NOT, NO WORRIES