The standard full scan is 63 minutes or that scan broken into 4 parts is about 16 minutes per part. These are all in the biofeedback folder of the Preset tab.
If you want to do the full scan in 2 parts, about 32 minutes each, then you would have to change the end frequency of the first part to 114000, and the start frequency of the second half to the same number with all of the other settings the same.
Otherwise, you are asking about a different scan that I am unfamiliar with.
For more details, please check the link: