Both Alstierers and Legbar/Welsumer crosses can be single combed with white earlobes. That's why leg color is important for distinguishing between the two. Alsteirers will not have yellow legs.
If the legs of these pullets are white rather than yellow then they could be Altsteirers. That's a rare European breed offered by Greenfire Farms for a while. It's an off chance but I thought I would mention it as a possibility.