As for calling the Cihuatlán numbers, you can call them, but I don't know if you will be given an appointment as you are not residents of Cihuatlán municipality. I know some people got them on the first day or two but supposedly that has been stopped to stop people jumping ahead of their municipality's turn.
The IMSS clinic in Cihuatlán is located on the street Primero de Mayo, to get there you take the lateral heading towards town and turn left at the traffic lights by the graveyard, it is a couple of blocks up on the left.
There is a lot of uncertainty at the moment and solid info is hard to find. What I have written is from what I have been told when I phoned up for my mum and first hand experiences from friends who have been.
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