Is it posible one Credit Limit assign multiple Customers

Hi Experts,

I have one Req: There is a multiple customers like A,B&C these are customers is having one credit limit only.

Ex: Business is giving for these customers for 1 Cr.

now If A customers is using credit, he is having some open sales order,delivery at this time system needs to block those customer credit limit and release limit to respective limit to other customers.

Is it possible in SAP slandered.

If yes how it is could you please explain me.

Thanks in  advance,

Ranga