Whats the demerits of U2L_CSFB_FAST_RETURN_PROC_OPTI_SWITCH in Huawei Vendor?

3G / 2G
1

U2L_CSFB_FAST_RETURN_PROC_OPTI_SWITCH is off in my network im gona to on it i wanna to know about the adverese impact of it in network?