cooltexas60s
Newbie
@vishalrao old 4G Sims are being asked to be replaced because of Volte and SRVCC(Single Radio voice call continuity). Once Volte is launched on Airtel 4G network and the user goes out of 4G network range in the middle of the call and lands on 3g/2G network then call continuity should be maintained and sim should support this. Else old sim will continue to lose network and keep hoping 3G and 2G network with delay and phone will keep searching for better network.