Hello, ref. VOA 30 days extension -

my landlady told me I shouldn't go less than 2 days before exit stamp to the embassy because one of her costumers got the extension stamp only 30 days from the very same day and the visa period got shortened.

Is this actually a common procedure?

Last year we went 2 weeks before, didn't happen.

Thanks

Edit : all went well, they even have a little sign saying check your new stamp, plus the officer showed me, and I Calculated the date in advance, the longest waiting was the tm30 part