Since day-based billing mode accounts subscription terms in units of days, on switching to it from millisecond-based billing mode, all start timestamps in Chargebee such as subscription start/activation/renewal timestamps and trial start timestamps are changed to the beginning (00:00:00.000 hrs) of the day. Further, all term end timestamps in Chargebee are changed to the end (23:59:59.999 hrs) of the previous day. Again, the time component is only indicative; any proration calculations in day-based billing mode are only done to the day.
Changing the billing mode on your test site is allowed but for switching billing modes on the live site, please contact support@chargebee.com
