Here's my suggestion:
First, the subscription needs 2 charges:
First, when creating the subscription, create a one-time charge $100 * 50 = $2000, effective 1/1/2016
Next, create a New Product amendment for a recurring charge $20 * 50 = $1000, effective 1/1/2017
On June 1, 2016,
Create a New Product amendment to add the one-time charge of $100 * 20 = $2000, effective 6/1/2016
Then, create a Update Product amendment to change the quantity of the recurring charge to 70 units, effective 1/1/2017
In the end, there will be 3 amendments and that should get the invoice schedule you want.
Fred
... View more