Torque converter shudder with disengagement

Hi everyone,

I've racked up 87,000 trouble-free miles on my 2017 4x4 DC, the last 25,000 with Magnuson supercharger. The transmission had an upgraded IPT toque converter installed @ around 72,000 miles. All has been well until about 100 miles ago, I noticed this distinct jolt when I let off the gas @ around 40-45 mph. Transmission is in 6th gear with converter locked and there is a pretty harsh jolt when the TC unlocks.

A fluid sample has been mailed to Blackstone (no results yet) to determine if coolant is in the fluid. I've read other threads here and on other sites about this exact same issue.

But none of them have specifically said if this is harmful. Is it?

Or what the exact cause is. Any ideas?