Receive invoices matched with POs encumbered to next year

Hi Gurus

I am looking to best practice for my business case

My budget is yearly and I have budget for 2015 and next year 2016.
I created a Purchase Requisition (or Purchase Order), using GL_date in 2015 and 2016.The system created encumbrance journals for 2015 and 2016, without problems.

I received invoices using total encumbered amount from 2015  and PART OF 2016 encumbered amount.

Example
2015 - encumbered  100,000
2016 - encumbered  150,000

Invoice 2015 - 150.000

The core system allows to receive this invoice and will generate 2015 encumbered -150,000  Actual +150,000

My customer wants to the system not allowed use next year encumbered amounts.
Is there any setup to prevent this ?