Reverback BI Workbook Conversion from 3.x

Friends,

we are on 3.x and upgraded to BI. For testing purpose we have converted on 3.x Workbook into BI format. Now that Workbook can open in BI analyzer only.. not with 3.x analyzer tool.

Is there any way that we can revert back the changes so that the Workbook can be executed back in 3.x analyzer. Is there any FM/Transaction/Program can help to do this.

Thanks

Mavip