Thunderbolt is dark as fuck, wow. So many disturbing moments in such a short time. I'm not sure if I buy it fitting into the OYW... seems weird to see such advanced Mobile Suits and Gundams around during that war. It always seemed like the RX-78-2 was the only Gundam at that time.
But this was great - the animation and soundtrack were so on point.
Well, I don't take Thunderbolt too seriously or canonically. Also, the way the OVA ends doesn't happen in the manga. Propulsion booster that are never used otherwise and the tech is pretty advanced for the period on the Gundam and Psycho Zaku.