What is your source for that?
Well, I’m not sure if it’s a credible source or not. You know you can’t really trust the US Military to tell the truth these days. But here’s one link.
https://www.7atc.army.mil/JMTGU/
“Mentor and Advise Armed Forces of Ukraine Trainers: U.S. Soldiers, joined by NATO allies and partners, mentored and advised Armed Forces of Ukraine Observer Controller / Trainers at the Combat Training Center located near Yavoriv. This was accomplished by employing a “train-the-trainer” approach, enabling Ukrainians to take the lead in training rotational brigades.
“Enable Combat Training Center Capability and Capacity: U.S. Soldiers worked with Armed Forces of Ukraine partners at the Combat Training Center - Yavoriv to develop and implement systems to improve combat training and increase training center capacity. Combat Training Center - Yavoriv delivered Brigade-and-below collective training for Armed Forces of Ukraine Brigades.”
Not like this is any secret, is it?
Yavoriv is in Lviv Oblast, UKRAINE.