"Due to the high demand of orders, this service is currently not available. "
I would take any quote like that with a pinch of salt, they may have just wanted to test the waters with small order and then look to roll out with larger numbers when demand is proven.
Given the complete failure of the government to provide any antibody testing, and the fact I've had this link sent to me three times already today, I very much doubt it.
"Due to the high demand of orders, this service is currently not available. "