Not true! :)
Access to your site might be restricted until you upgrade or bring the tree within the limits of the free site, but we never, ever delete your data.
And you can always get a copy of your tree on the Family Tree > Manage Trees page even if access to the site is restricted.
Rihanna, I have a family meeting in two weeks. please expand my space to unlimited as per my subscription plan.
Write this problem to firstname.lastname@example.org
This is the better way.