MK 111 leaking soft top -update - check your vin numbers!

A few weeks ago I discovered my 23 month old MX5 footwell was 3" full of water!. Found out the drain holes were blocked and was charged £37.00 plus vat to unblock  drain holes (even though still under warranty) by local dealer . After several replies to my posting on this forum (many thanks folks) found out this is a problem with the MK111 and a modification can be done - a filter is added to the drain assembly to prevent leaves or other debris from clogging the drain. I contacted my local dealer with this information and was told ( re my vin number ) that my car already has the modification- so why is my car full of water??  Several phone calls to other dealers later I discovered that in fact my car DOES NOT have this modification.   If you have a MK111 and the last 6 digits of the vin number are less than 129271 then you should enquire re modification.  This is found on Mazda service bulletin . Bulletin number 19 under the heading- Water leaking- water in cabin from soft top. This information was disclosed by a Mazda dealer and is not available to customers.  I finally had the modification fitted yesterday but only after several calls to my local dealer.