Prevent date if it is later than January of following year

Does anyone have a script I can use to prevent a user from entering a date (in mm/yy format)  that is after 01/?? (?? being the following year) 

In this particular case the user is entering 2 dates, an effective date and an expiration date. The expiration date should never be after January of the year following the effective date.

Examples:

If the user enters 11/14 (mm/yy) as the effective date, they should not be allowed to enter an expiration date past 01/15

If the user enters 01/15 (mm/yy) as the effective date, they should not be allowed to enter an expiration date past 01/16

Thank you so much in advance for your help.