Not so. SS options are varied one person per seat/spac, 1and a half or two per seat space ,which may emerge as options for the Amex. An increase in capacity would not require re modelling anything. I am sure that Exits, egress, concourses, stairs etc are built to fire regs not numbers of people, although it is a factor. The North stand could go 70% SS with normal seats for those who want them, with any of the above options for SS. If numbers were a problem we could just sick with one person per SS seat/space.
Id answer in exactly the way driver8 already has. The club have said time and again that capacity will not change with safe standing and nor would cost per space. I wasnt just saying it for the fun of it.