For the pedestal design, it limits the maximum spacing of pedestal reinforcement to 6". Why is it restricted to user definition? Probably because of this constraint, reinforcement provided is way higher than required. Almost 10x the moment demand. PDF
Please note that the "maximum pedestal bar spacing" is not a fixed value for ACI 318 code. You can enter the required value of spacing by typing. See the attached screenshot with a 10" spacing
Pedestals in SFA are designed as short columns. The area of steel for this pedestal is governed not by bar spacing, but by the minimum reinforcement criterion (1% as per 10.6.1.1 of ACI 318-2014). Notice that the steel provided is 1.02%.