Can conservation laws take time to obey?

[Dark85]

TL;DR

Can conservation laws take time to obey?

Hey everyone, I have a question
During a process, there are certain quantities that have to be conserved like energy, momentum(assume there is no external impulse and hence momentum is conserved) etc. Can these conservation laws take time to obey i.e. the quantities can be conserved during a certain amount of finite time as long as they are conserved at the end?

 

[Baluncore]

Can these conservation laws take time to obey i.e. the quantities can be conserved during a certain amount of finite time as long as they are conserved at the end?

Since the laws must hold between the start and half-time, and between half-time and the end, conservation must be a continuous process.