Setting up status automatically with allocation of resource in MRS

Dear MRS experts,

Need a guidance over the Abstract status setting in MRS. The requirement is to set an status, say RES_ALLOCATED automatically , once the resource has ben allocated to an operation, into MRS planning board . I don't need to set it manually for each operation. Its should be set immediately once a resource is assigned to an PM order demand operation.

Can someone guide here how to achieve this??

Thanks