ZenTimestamp Plugin 4.1 throws NullPointerExecption after updating P4 Plugin from 1.2.1 to 1.2.4 (which depended on SCM API Plugin 0.2 being installed as well)

Stack trace in job log:

...
P4 Task: establishing connection.
...
FATAL: null
java.lang.NullPointerException
at hudson.plugins.zentimestamp.ZenTimestampEnvironmentContributor.buildEnvironmentFor(ZenTimestampEnvironmentContributor.java:57)
at hudson.model.Run.getEnvironment(Run.java:2248)
at hudson.model.AbstractBuild.getEnvironment(AbstractBuild.java:935)
at org.jenkinsci.plugins.p4.tagging.TagAction.<init>(TagAction.java:40)
at org.jenkinsci.plugins.p4.PerforceScm.checkout(PerforceScm.java:282)
at hudson.scm.SCM.checkout(SCM.java:485)
at hudson.model.AbstractProject.checkout(AbstractProject.java:1276)
at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(AbstractBuild.java:610)
at jenkins.scm.SCMCheckoutStrategy.checkout(SCMCheckoutStrategy.java:86)
at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:532)
at hudson.model.Run.execute(Run.java:1744)
at hudson.model.Run.run(Run.java:1682)
at com.cloudbees.plugins.flow.FlowRun.run(FlowRun.java:153)
at hudson.model.ResourceController.execute(ResourceController.java:98)
at hudson.model.Executor.run(Executor.java:374)