I was also re-invited. I did 184,000 PQM spend around $45k mostly from January - July on LATM, EU and SFO flights.
I moved from ORD to BOS at the end of June this year so ended up doing another 180,000 on LH and credited those into Miles & More. It really sucks not having a UA metal option from Boston Logan to Europe. I was not expecting to re-qualify when I started solely flying LH & LX to Europe in July.
I found this this re-qualify email a very nice surprise and Christmas present from SMI*J.