Is it a big risk if we have different schema version of AD in prod and pre-prod environment

Hi Experts 

We are using Identity manager version 8 and We have two AD one for Prod and another for non-prod. Both are align to same schema version that was 47

However Recently there are some changes and non-prod AD upgraded to schema version of 87. If we have two different schema version then what are the challenges we might have going forward?

Can you please help?