Generally, for as long as there is nothing left to debate about.

When “Germany” debates something, especially “terminology,” they will do so until the cows come home. And then leave home again. And then come back home again. And so forth.
For 15 years now, the term used by German statisticians and politicians alike to denote foreigners and their descendants has been “people with a migration background.”
That was the label given to people who weren’t born into German citizenship. And to people whose mothers or fathers were not born German citizens. Today, that applies to a quarter of the population.
After two years of discussing how Germany could better acknowledge its status as a society of immigration, a SPECIALIST commission of 24 politicians and academics appointed by the government has submitted its report to Chancellor Angela Merkel. One of its recommendations is to stop using the terms “migration background” or “immigrant background.”
People should use the term “immigrants and their descendants,” commission chair Derya Caglar said. “In my case, this would mean that I am no longer the migrant, but rather the daughter or descendant of migrants.”