Mashable claims to have gotten some clarifications from Yahoo, and indicates all Pro accounts are 'recurring' except perhaps gifted memberships.

"Can I Still Keep my Flickr Pro Account?
Yes. Last year, Flickr migrated all Flickr Pro accounts into recurring accounts. As long as your account is by way of a recurring subscription (currently quarterly, yearly or for two years), you can continue to renew your account once it expires."

http://mashable.com/2013/05/20/flickr-pro-changes/

Hope so...