Alright, I got bored, and I think we can safely put the Hesco 3885 theory to rest. LTC was awarded new contracts by USSOCOM in 2023 (H9240323F0113 & H9240323F0115) for Tactical standalone plates. These are either GEN-6 or GEN-6B. It does not specify whether these are TSA/Overt (example - 28595, GEN-5) or TSA/LTO (example - 28791 GEN-5). These are usually awarded as a pair. TSA/Overt is B-32 API, TSA/Lessthanovert is 2x BZ API / M855A1 with M80 on the side.
Projected weights going off of past TSA iterations are as follows.
GEN-6 Tactical Standalone - 4lb for SOCOM medium swimmer, single-hit B-32 API protection or 2x BZ API. Prior GEN-5B awarded to VelSys is 4.4lb. LTC 28595 (GEN-5) is 4.85lb. GEN-6B would be 3.8-4lb depending on how far along "black side" PE development is. Boron carbide is boron carbide, so unless they've got a new ceramic up their sleeve or some new additives you cannot thin the strike face - the heaviest component. Boron suboxide development has been quiet lately...
TSA/LTO:
GEN-5 plate is the LTC 28791, 2x BZ API, no capability against B-32 API, with multi-hit capacity against M855A1 and other lesser threats. 4.13lb for a swimmer medium. GEN-5B is honestly pretty likely the VS-PBZSA, which by my calcs is 3.9lb for a swimmer medium. GEN-6 is projected 3.7, GEN-6B 3.5-3.6lb.

While this is long and pointlessly autistic, the point in play is that if you wait a year or two, there will inevitably be some seriously gucci shit showing up "surplus." I am cautious on the GEN-6B calculations because I am unaware of any serious ceramic advancements on LTC's side and Honeywell's improvements to spectra shield with the latest 6000 series have only been incremental.
As a particular fellow armor autist would be happy to hear... the 28855 is predictably a phantom. Probably the same situation as the 3885. It is either nonexistent or exists at a level so arcane it will never, ever show up... "second hand" and is therefore functionally nonexistent.