You can export your notes to iTunes over wifi.
1-Connect iPad to the computer
3-Select iPad from the top right of the library. In the "Apps" section at the top of the library, choose Notability
4-Scroll down to the File Sharing window
5-Open Notability on the iPad and tap the export button in the upper left of the library. It looks like an arrow going out of a square
6-Select iTunes from the export options.
7-Select the notes you would like to export and the format for the notes
8-Tap "Send to iTunes". Your exported notes will appear in the file sharing window in iTunes. You can then drag the notes to your computer desktop or another folder on your computer.