My friend got his ip5 on Fri after, phone only shows 3G. He thought its coverage problem staying in Hougang. So on Sat he went down to Chinatown and walk to Clark Quey then Funan and the phone still 3G, no sign of LTE. Called first SingTel CSO and the guy asked him to try reboot ip5 and tried. Called second CSO, and this one said will escalate the problem, and someone would call on Sat/Sun.
So my friend wait one day, no one called, phone still 3G, never LTE. He worried ip5 hardware problem. Called third Singtel CSO. And this one said case escalate to coverage team, someone will contact him in 5/6 days. This third one tried to explain that if too many people trying to sign on to LTE then my friend will not get signal.
I asked my friend to call again to confirm his line is set to 4G. He called forth CSO, this one checked and said his line is 4G enabled already, and the same message that someone from coverage team will call him.
My friend went outside after his call to CSO, and his phone got LTE before stepping into the lift. It's 4/5 bar at hougang central.
So check your ip5 got at least LTE enabled, apparently something need to be switch on at telco side, or else you will keep using 3G.