Not necessarily. I'm fairly sure that was the first time Melbourne got Lawson's promo, so I'm referring to the fact that he might actually be "Housemate #5" (officially). The OS hasn't uploaded his video yet, so chances are he's tonight's HM's - by social media's pov.
In saying that, the first ad break of The Block is on right now as I type, so we'll know for sure shortly......
Hopefully it's him.
Can't be bothered investigating tonight xD