Calling engineers back to USA doesn't make any sense, unless it was made as preparation for an imminent war.
Saying this because a few days ago the minister of the Romanian defense has resigned, for the reason that he can not collaborate any longer with the Romanian president which is also the supreme commander of the Romanian army. The now resigned former minister was advocating for peace. Meanwhile, an elite USA attack division, 101 Screaming Eagles (about 5000 US military) are doing exercises in Romania, plus more NATO troops in Romania, from France. Romania has common border with Ukraine. Meanwhile Russia announced it finalized its first stage of general mobilization of 300 000 new recruits.
I didn't follow the news for a couple of weeks, and yesterday learned about the resignation of a minister that was advocating for peace, and today I learn about the calling home of US chip specialists. I'm very worried about all these.