Version Found: MIG 7 Series v4.2
Version Resolved: See (Xilinx Answer 54025)
In Vivado 2019.2 and later versions including Vivado 2020.1 and 2020.2, the MIG IP GUI does not allow the system clock (input clock period) to be customized.
This behavior can be corrected using the tactical patches attached to this Answer Record.
01/08/2021 - Initial Release