I have 2 data sources. A and B.
Each data source has 2 data points: A_1,A_2,B_1,B_2
I have 2 point links:
A_1 -> B_1
A_2 -> B_2
If I delete point A_1, then point link "A_1->B_1" is not shown in point link list. Then I can't delete this point link but "Point link source is unavailable" alarm is raised.