Visa - multiple entry (Manama)

Hi guys,

I'm looking for a bit of info regarding a multiple entry visa. I came into Bahrain on a on-arrival 3 months visa with my British passport, since then I have received my CPR and multiple entry visa but a stamp next to the multiple entry visa states "Valid for 5 years from date of issue - Stay must not exceed 4 weeks"

So does this overrule my most recent 3 months visa which I only received on the 12th of Feb, for a 4 week visa? Or will I be able to stay the 3 months from my last entry and then thereafter immigration will only give me 4 weeks when I re-enter as per the stamp?

Any help would be appreciated.