Thanks chaps. I have created a backup from within Xpenology DSM and just awaiting delivery of Synology box. Thus far it has been relatively pain free. Initially I had a concern as data usage was approx 8tb and I didn't have storage that large for backup, but found cloudsync was eating more than half that. So post getting rid of dead data, created a backup which took a night.
I'll update you once I have an update. A big thanks to this site and members, I definitely would be lost if it wasn't for you. All your help and patience is appreciated.