@David Briars as far as I recall this is something that was added in 9.30 for XLSX.
From the release notes - https://docs.tibco.com/pub/wf-wi/9.3.1/IBI_wf-wi_9.3.1_relnotes.pdf
"Positioning Components in Excel Documents You can now position Components in an Excel Compound document. You can position items on multiple worksheets or a single worksheet, and items can be positioned in a fixed location by cell, or relative to each other. For more information, see the ibi™ WebFOCUS® Creating Reports With ibi™ WebFOCUS® Language guide."