First the disclaimer - since these are often replaced, swapped with other cars and depending on the angle can be hard to see that third screw no since observation should be used as hard evidence
With that said - went through my pictures and found the following
Earliest three screw versions I found were from 1/31, 2/2 & 2/7
Latest two screw versions I found were from 2/7, 5/11, 5/19
Last two dates appear to be out of range and are possible false leads
(all actual completion dates)