Export Tiled Artboard as PDF and Retain Layers.

Hi There, 

I'm working with Illustrator CS6. I'm drafting sewing patterns in several sizes which sometimes are larger than A4.

I need to export these layers into 4 x A4 PDFs tiled from my larger artboards, as they are to be part of a complete A4 document. I am able to tile the artboard and not retain layers in the PDF or retain layers in the PDF and not tile the artboard.

I have tried printing to postscript and converting in distiller. and have tried exporting and saving as to PDF with tiles in more ways than I can remember.

Any advice would be greatly appreciated.

If this isnt possible.. is there a way I can seperate my A2 artboard into 4 A4 and split my objects with them?