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- Create or edit package in Settings->Products and services
- Change package Price to free - preview
- In Automation tab add custom task: "Change account billing cycle"
- In Automation tab add custom task: "Increase Change account recurring price"
- Under "Automatic suspension" set email that needs to be sent to client after suspension (i.e. "Your free trial is over"), and set auto-suspension to 1 day after due date
- Add another custom task - Send email 30 days after account creation to inform customer that his free trial is over
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