As of 23rd of June 2015, Fedora 20 has reached its end of life for
updates and support. No further updates, including security updates,
will be available for Fedora 20. A previous reminder was sent on
27th of May [0].
Fedora 21 will continue to receive updates until approximately one
month after the release of Fedora 23. The maintenance schedule of
Fedora releases is documented on the Fedora Project wiki [1]. The
Fedora Project wiki also contains instructions [2] on how to upgrade
from a previous release of Fedora to a version receiving updates.
Kevin
[0]
https://lists.fedoraproject.org/pipermail/announce/2015-May/003267.html
[1]
https://fedoraproject.org/wiki/Fedora_Release_Life_Cycle#Maintenance_Sche...
[2]
http://fedoraproject.org/wiki/DistributionUpgrades