Sequence node numbering error when adding execution pin.

When using the "Insert execution pin after" option with a sequence node "Then 0" gets removed.

1. Open up the level Blueprint and connect a sequence node to EventBeginPlay
2. Add a few extra pins to the sequence so there are 6 total (0-5)
3. Right click "Then 3" in the sequence node and select "Insert execution pin after"

Result: The pin is added as expected but "Then 0" is removed.

Expected: The extra pin is added without replacing 0.