Upon upgrading from subversion plugin 1.54 to 2.4 (w/ credentials plugin 1.14), I receive this exception on startup

Caused by: java.lang.AbstractMethodError: hudson.scm.SubversionSCM$DescriptorImpl$Credential.toCredentials(Lhudson/model/ModelObject;Ljava/lang/String;)Lcom/cloudbees/plugins/credentials/common/StandardCredentials;
at hudson.scm.SubversionSCM$DescriptorImpl.migrateCredentials(SubversionSCM.java:1676)
at hudson.scm.PerJobCredentialStore.migrateCredentials(PerJobCredentialStore.java:109)
at hudson.scm.SubversionSCM$DescriptorImpl.migratePerJobCredentials(SubversionSCM.java:1657)
at hudson.scm.SubversionSCM.perJobCredentialsMigration(SubversionSCM.java:1589)
... 13 more

Full stack trace: https://gist.github.com/recampbell/1e4b4462ada0ca6662d4