Production status parameter removed from search results?

I know in the past, the addition of

"&production_status=released"

did exactly what the words say, namely exclude unreleased films in search results. However, I did not find this setting in the search options anymore and also adding the parameter manually does not do the trick here. Anybody knows a way to get it back? The only somewhat workaround I can think of right now is including this very day as the latest release date, but it's not really practical because you have to change it every day.