My experience trying to upgrade from both RC1 and RC2-SNAPSHOT is anything but painless.
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 10.468 s
[INFO] Finished at: 2016-09-20T07:23:28-04:00
[INFO] Final Memory: 11M/357M
[INFO] ------------------------------------------------------------------------
[ERROR]
Failed to execute goal on project cas-overlay: Could not resolve
dependencies for project org.jasig.cas:cas-overlay:war:1.0: The
following artifacts could not be resolved:
org.apereo.cas:cas-server-webapp:war:5.0.0.RC2,
org.apereo.cas:cas-server-support-gauth:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-gauth-jpa:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-captcha:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-ldap:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-jpa-service-registry:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-jdbc:jar:5.0.0.RC2: Could not find
artifact org.apereo.cas:cas-server-webapp:war:5.0.0.RC2 in
sonatype-releases
(
http://oss.sonatype.org/content/repositories/releases/) -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException:
Failed to execute goal on project cas-overlay: Could not resolve
dependencies for project org.jasig.cas:cas-overlay:war:1.0: The
following artifacts could not be resolved:
org.apereo.cas:cas-server-webapp:war:5.0.0.RC2,
org.apereo.cas:cas-server-support-gauth:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-gauth-jpa:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-captcha:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-ldap:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-jpa-service-registry:jar:5.0.0.RC2,
org.apereo.cas:cas-server-support-jdbc:jar:5.0.0.RC2: Could not find
artifact org.apereo.cas:cas-server-webapp:war:5.0.0.RC2 in
sonatype-releases
(
http://oss.sonatype.org/content/repositories/releases/)
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.666 s
[INFO] Finished at: 2016-09-20T07:24:38-04:00
[INFO] Final Memory: 14M/357M
[INFO] ------------------------------------------------------------------------
[ERROR]
Failed to execute goal on project cas-overlay: Could not resolve
dependencies for project org.apereo.cas:cas-overlay:war:1.0: Failure to
find org.apereo.cas:cas-management-webapp:war:5.0.0.RC2 in
http://oss.sonatype.org/content/repositories/releases/ was cached in the
local repository, resolution will not be reattempted until the update
interval of sonatype-releases has elapsed or updates are forced ->
[Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException:
Failed to execute goal on project cas-overlay: Could not resolve
dependencies for project org.apereo.cas:cas-overlay:war:1.0: Failure to
find org.apereo.cas:cas-management-webapp:war:5.0.0.RC2 in
http://oss.sonatype.org/content/repositories/releases/ was cached in the
local repository, resolution will not be reattempted until the update
interval of sonatype-releases has elapsed or updates are forced
-Jeff