Are you sure this would not cause problems if two devices with the same IMEI were on the same tower, or even same provider? It might look fishy having multiple dups floating around on your network.
If one of these devices gets IMEI blacklisted, now all 13.5K devices are blacklisted... Not so good.
If one of these devices gets IMEI blacklisted, now all 13.5K devices are blacklisted... Not so good.