2 days7 days30 daysBy Industry Show more Advertise your job vacancies Call centres are increasingly using mobile numbers for outbound calls — an effective tactic, but one that goes against regulations, potentially damaging brand reputation and public perception. Infringement The Icasa 2016 Numbering Plan Regulations prohibit the use of mobile phone number ranges such as 082, 083, or 072, for example, for fixed-location services such as call centers.