" Yahoo Pipes: Pipes creation will not be supported as of Aug. 30 this year. Pipes infrastructure will run until Sept. 30, 2015 in read-only mode to help developers migrate their data. Please visit http://pipes.yahoo.com/pipes for additional details."

from http://yahoo.tumblr.com/post/120700756894/q2-2015-progress-report-on-our-product

Deadline is thus August 30th - we should before that have migrated all feedburners that pointed to our yahoo pipes to something else.