Arranging : Time, Tempo, Meter, Key, and Chords : Insert Time : Insert Time Options

Insert Time Options
Options for the Insert Time command include:
Start, End, and Length
Sets the start and end points for the selection, and the selection length.
Set Meter
If your Main Time Scale is Bars|Beats, Set Meter lets you specify a new meter for the inserted time. The selection is quantized to the nearest bars, and the previous meter is inserted after the selection. If your Main Time Scale is sample-based, Set Meter is not available.
Realign
The Realign settings let you select which items shift (occur later) when time is inserted, as follows:
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If your Main Time Scale is set to Bars|Beats, you can choose to realign meter events only, or choose to realign a combination of Meter and Tempo rulers, all tick-based markers and tracks, and your choice of sample-based tracks.
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If your Main Time Scale is set to an absolute timebase (such as Min:Secs), you can choose to independently realign conductor events, tick-based markers and tracks, and your choice of sample-based tracks.
Meter Ruler Only
If your Main Time Scale is Bars|Beats, you have the option to insert time into the Meter ruler only. Meter events after the start point of the selection are shifted past the end point by the length of time selection.
If your Main Time Scale is sample-based, Realign Meter Ruler Only is not available.
Meter, Tempo, Key, and Chord Rulers, Tick-Based Markers and Tracks, and Sample-Based Markers and Tracks
Lets you insert time into the Meter, Tempo, Key, and Chord rulers, and all tick-based markers and tracks. Events after the start point of the selection are shifted past the end point by the length of time inserted.
If the Timeline selection includes any audio clips on tick-based tracks, the audio clips are separated at the Start point, and the new clip containing the previous selection is shifted to the end point.
Using the pop-up menu, you can also choose to insert time into All or No sample-based markers and tracks. If All is selected and the selection includes any audio clips on sample-based tracks, the selected portions of the audio clips are separated at the Start point, and the new clip containing the previous selection is shifted to the end point.