It's really unclear but from this paragraph in the email it sounds like the whole organization will be "subject to deletion":
> If you don’t upgrade to a paid subscription, Docker will retain your organization data for 30 days, after which it will be subject to deletion. During that time, you will maintain access to any images in your public repositories, though rate limitations will apply. At any point during the 30-day period, you can restore access to your organization account if you upgrade to a paid subscription.
> If you don’t upgrade to a paid subscription, Docker will retain your organization data for 30 days, after which it will be subject to deletion. During that time, you will maintain access to any images in your public repositories, though rate limitations will apply. At any point during the 30-day period, you can restore access to your organization account if you upgrade to a paid subscription.