@Sean ******
At least I can tell you that immigration offices have access to your visa data.
How do you think they would give an extension on something they don't have access to.
You claim immigration does not have access to visa data, so maybe you should explain how it is possible a lot of people here say they did not even need to show their visa and just got an 180 day stamp.
But when I ask you for an explanation on this, you just chicken out...
You are the one claiming things here, I did not start claiming anything here, only asking you for proof of your claim that all visa are equal unless there is a remark.