Remove node A from swap 16162 and convert to triangle

Hi. 
In swap ID 16162 (square), Node A never opened channel and has been missing for 2 weeks.
Nodes B, C and D have come to an agreement to convert the swap from Square Capacity (4 participants) to Triangle Capacity (3 participants). 
Node D, closed channel to A and opened to B.
Please remove Node A, and convert the swap to Triangle. I am not aware if starting a new (Triangle) swap without re-opening channels is an option.