Extension of Mother's Visa

Hi,

I would appreciate to solve a puzzle. My mother is 74 years old and I applied and got her visit visa from the main immigration office. She is here now and today I went to Abu Hamour Immigration Office for the extension of her visa for another 5 months. I requested to extend the visa for 5 months but the lady behind the counter said can be extended for another 2 months. I asked last time when my mother visited she stayed for 6 months, has the law been changed? But I did not get any answer? Does any one know if there is a change in the law about the duration of parents stay? I would appreciate your help very much.