Waiting Period

We've just joined Discovery Health as of 01/08/15 We were previously members of Discovery from 01/01/10 - 30/09/13 We moved to RUMED because my husband was retrenched by Pioneer Foods and he was the main member. Before joining Discovery the kids and I was on Bankmed. I received a copy of our Membership Certificate and it shows that there is a 3month waiting period as well as a 5% late joiner fee for my husband. When we joined Discovery in 2010 we didn't have any of these. When I joined RUMED they wanted to impose the 3 month waiting period, but because I could prove that we had uninterrupted cover the waiting period was waived. I received my Membership certificate from RUMED last week for the termination of membership and they show no limitations on the certificate. Why is it that we should wait 3 months now if we still have uninterrupted medical aid cover? Thanking you Raylene Swanepoel