When upgrading from plugin version 3.1.6 to 3.1.7 we have run into the following error. 

FATAL: Failed to push the build information: java.lang.NullPointerException
java.lang.NullPointerException
at hudson.plugins.octopusdeploy.AbstractOctopusDeployRecorderBuildStep.getOctopusDeployServer(AbstractOctopusDeployRecorderBuildStep.java:240)
at hudson.plugins.octopusdeploy.OctopusDeployPushBuildInformationRecorder.buildCommands(OctopusDeployPushBuildInformationRecorder.java:135)
at hudson.plugins.octopusdeploy.OctopusDeployPushBuildInformationRecorder.perform(OctopusDeployPushBuildInformationRecorder.java:118)
at jenkins.tasks.SimpleBuildStep.perform(SimpleBuildStep.java:123)
at org.jenkinsci.plugins.workflow.steps.CoreStep$Execution.run(CoreStep.java:101)
at org.jenkinsci.plugins.workflow.steps.CoreStep$Execution.run(CoreStep.java:71)
at org.jenkinsci.plugins.workflow.steps.SynchronousNonBlockingStepExecution.lambda$start$0(SynchronousNonBlockingStepExecution.java:47)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:829)