Hi

Thanks for the very kind offer.

I ran into a variety of related issues and in the end had a bash at formatting the data in Excel. I was able to do this after a flash of inspiration and so have solved the issue without needing to ask for further help.

The crunch was realising that processing in Excel was always going to be needed due to the many 1000s of rows of data and the need for conditional extraction of data for multiple mail merges and iterations over the data.

With the very best regards

Lorenzo