Thanks to TwilightSparkle for this one.
Apparently, Matilda BP turret got resized. Along with a depression buff, the turret itself is noticeably smaller, have a look (to the left - 0.8.6, to the right - 0.8.5). It's also visibly shorter, so let's hope this finally makes Matilda BP a bit more enjoyable to play. Turret armor got also buffed, from 76/51/44 to 76/63/57.