BL1 not showing correct dates - sorted Now

Morning all, 

I've recently had installed a newer (17.3) version of P6.  I've got a copy of a submission from last month which I'm comparing to a submission this week.  However for some reason the dates aren't coming through correctly.

I've assigned the old one as BL1 and as there is no change in a LOE activity date I'd expect it to show the same but for some reason it's showing a date a year out.   Other dates are out too and I cannot understand why it's not all as some are fine.

Any advice folks?

Thanks

EDIT - it was the earned value setting.