NOTE: It's briefly mentioned in this video, but keep in mind that if you are using a non-Adobe tag management solution, then you basically need to treat appMeasurement updates as if you were using NO tag management solution. In other words, wherever you have your appMeasurement code, that is the place that you would do the update. If you are using Adobe Launch, then of course the update is quick and easy and no code needs to be copied or pasted. But if you are not using Launch, then yeah, you need to retrieve the new code and replace the old code in the file or in the TMS.
This video shows you how to update your appMeasurement code when you are not using Adobe Launch. This includes where to get the code and where to update it.