You may be running a intro course or specialty course that starts on a specific date. This is how you can define the start date for people signing up.
This parameter is not set on the plan template, but rather when the plan is added to a person at time of signup.
Option 1. Creating a link to sell this Plan online
Navigate to the Plan detail page.
Click the 'View Page' link in the right column, located under the title 'Landing Page'
This will pop up a modal where you can configure a couple of variables. One of them is 'Optional Start Date'. Toggle this to YES.
Select desired 'Start Date' from the date picker.
This will create a unique URL, and when used will automatically set the official start date of this plan to what you selected.
Option 2. Adding Plan to member through Control Panel.
When you get to the plan add page, set the 'Start Billing; field to the desired start date.
Thats pretty much it, there is no step 2.
The 2nd method above will charge the person on the start date you selected. The 1st method will charge the person instantly for the first payment (if its a recurring plan), but will adjust out all subsequent bills from the start date selected.
If the plan has an expiration date, example, good for 3 months. This date will be calculated from the start date in both cases.
This online Landing Page mentioned above is different than the plan page in the Member Portal. Currently this method of pre-defining a plan start date is not available through Member Portal.