Excel export problem

I've got 7.2j.1 installed.

If I export a report to Excel as XLSX it is interpretting some of the results as dates when they're not. So values like £190,116 is being interpretted as 19/01/16 by Excel and causing problems when summing the column. I can get around this to a point by exporting to CSV (Not Excel CSV) and having my tab delimiter set to a semi-colon (not sure if that bit had any effect) and it gives me the data just fine but obviously no formatting and the user would rather like the formatted output.

According to the 7.3sp2 release notes, a problem was fixed in Excel exporting where incorrect formatting was applied to some or all cells - 0-166232-QA but I don't know if this is the same problem. It was ok when they were on 7.1. They've just upgraded to 7.2 and they're not going to 7.3 yet for various reasons, so does anyone have any ideas for a workaround or fix?

Thanks.