Duration values showing incorrectly when linked to another sheet
I wonder if anyone can help with an issue we have that has recently appeared.
We have many project plans within our business, and some key fields from those plans are linked to another source sheet that we use to build reports from. We have linked the total project duration field, but it is displaying in a very odd way in some instances. See example screen shot of total duration on a specific project plan which is showing as 431 days.
The total values on this plan are linked to another sheet, including the duration total, but it is showing as a very strange value of PT10344H. It happens on random values as you can see a little further down. It is something that has only recently appeared without us having altered anything on the sheets and try as we may, we cannot explain why. The project plans are all created from templates that are re-used so all the ones with a category of endoscopy below are created from the same plan template and have the same owner. So we are stumped as to why some show a strange value, especially when it is just a cell link to the duration value as shown above.
Any help or advice would be appreciated.