Has probably been asked before on this very subsection, but I wanted to confirm: Brownells made a Portuguese-style mid-length handguard intended for the BRN-10s, but never seemed to follow it up with the correct rifle-length heatshield for it. This is what I want to confirm.

According to this Reddit post and publicly available information about the Portuguese AR-10s, its mid-length heatshield was supposed to go hand-in-hand with the rifle-length heatshield onto which it would clasp and be restrained by both the rifle-length gas block as well as the mid-length handguard retaining flange, an element of the heatshield itself.

Is this wholly accurate, and if so did Brownells ever plan on making those heatshields, or was this just 'another bridge too far' for the BRN-10 retro project before it was internally axed or something?

Hopefully someone with more knowledge than me will step in here.  The guys that I would ask are out of the office for the next 10 days or so.