New Subscribers Monthly!, page-3

You can kind of work this out from their quarterlies:

If we make some basic assumptions:
- no customers as at 1 July 2018
 - no revenue from the book
- all customers sign up at the monthly rate
- 30 day free trial
- new customers sign up on first day of quarter for simplicity

Sept Quarter:
- Receipts: $2K
- Customers: 125 (125 x 2 months with 30 day trial)

Dec Quarter:
- Receipts: $5k
- Customers: 250 (125 x 3 months, 125 x 2 months with 30 day trial)

If we were to spread out the onboarding throughout the month the number of customers would be slightly higher as the customer payments are less per quarter.