Expiry days

Hello Devs
In version 2.25 I have a data set with a period “annual” and expiry days set to 96, this works fine now for reporting 2016 but if I try to import data with a period 201601 the system rejects the data indicating the period is locked, It seems the expiration is being calculated based on the period of the data being imported (monthly, expiry 96) rather than period indicated in the data set, is this intentional?
Regards,
JM