How long does it take to get the QAS?

If I order the QAS (Question and Answer Service) for the SAT, when should I expect to receive it (how many weeks after the test date)?

If you order it with registration, you should get it within two months of the test date. From the College Board website:

"In many cases, Question-and-Answer Service materials may not arrive until after the next scheduled test date. Materials are typically mailed within 6-8 weeks of the test date if you order when you register, or 3-4 weeks after ordering if you do so after scores have been released for your test."

Source: https://sat.collegeboard.org/scores/verify-sat-scores