I don't think so, my mobile phone is always turn on for 24/7, but I always got SMS caller alert telling me someone trying to call me but were unbable to reach me.
I got s Singtel line.
There are many of my Singtel users' friend complaining about the congestion.
All of my M1 friends do not have this problem.
There are times my Singtel line lost signal altogether, but my M1 friends still manage to make and receive calls.
So what's your experience?