Canada Time Zone by Area code

EBS: 12.x.x

We have a requirement to fetch Canada Time Zone.

Few states in Canada have multiple time zones. E.g. ON has both ET & CT.

Back end table HZ_TIMEZONE_MAPPING doesn't have 'Timezone to Area Code' mapping for Canada.

It has only one timezone defined for each state.

Let me know if we can derive Time Zone by Area Code from back end.

Or How can we upload and maintain the information in E-Business Suite.

Thanks