Note that Beta 4 greatly increased all ship "module" components' masses. They went from mass 5 (ridiculously light) to mass 40-50 each. You can't even build an early double-ctor any more because the 2nd ctor module doesn't fit.
So maybe a "survey module" also got huge(r) in mass, and no longer fits the old survey ship designs. Maybe that causes the ship-generator function to just omit the survey module.