The Session Setup Window has a SMPTE offset entry area ("Session Start"), which allows you to set the SMPTE start time for your session. (There is also an area that lets you set the frame rate for your incoming time code.) If you get a tape to work with that contains a new SMPTE start time (a change from when you started your project), you can enter a new start time. When you do this, you will be prompted to choose if you wish to maintain the absolute positions of your on-screen regions relative to the time code on your tape (most common), or whether you wish to keep the position of your regions relative to the start of the session. For example, your session might start at 01:00:00:00 and you have a region at 2:10.000 (coincides with 01:02:10:00 on your tape). You then decide to move the Session Start earlier so that you can spot something to a location before 1 hr. Setting the Session Start to 00:00:00:00 will prompt you to Maintain Time Code (your region will now be at 62:10.000 and will still line up with your tape) or Maintain Relative Position (your region will still be 2 minutes and 10 seconds from the start of the session, an hour earlier than the location on your tape).