How to migrate from Jetpack Comment Subscriptions
We do not yet have a direct importer to migrate legacy Jetpack comment subscriptions to Postmatic. We may in the future.
For now there is an easy way to make the jump to Postmatic
A crafty workaround is to run both your old plugin and Postmatic side by side so that notifications to legacy subscriptions still get sent but new conversations will use Postmatic.
Step One: Install Postmatic
Installation is easy. If you aren't sure how to do it there is a tutorial here.
You'll now have two subscription boxes at the bottom of each post:
Step Two: Hide the Subscribe to Comments checkbox
In your WordPress dashboard, go to Settings > Discussion. Scroll down to Jetpack Subscriptions Settings and uncheck the box next to Show a 'follow comments' option in the comment form. Click on the Save Changes button.
Your comment form will now look like this:
Let Postmatic take over
Users subscribing to your comments from this point forward will receive notifications from Postmatic, but your legacy subscribers will still be in the loop as well. In a few months time it should be safe to disable Jetpack Subscriptions. And maybe we'll have a proper importer by then as well.