Hours after some M1 customers reported intermittent access issues with mobile data, the telco released a statement to confirm that the issue had been resolved as of 2PM yesterday. Apparently, voice calls, text messaging and 4G data services were not affected.
M1's preliminary findings suggest that a software bug prevented some customers from connecting to the mobile data network. The telco also stated the problem started at about 8AM yesterday morning "following a scheduled network upgrade" on Sunday's night.
The previous 3G service disruption on 16th October was due to to a radio network controller that the telco upgraded. This is the second time in two months that M1 customers had their 3G services disrupted in the morning.
Source: M1 Facebook Page