Component used: androidx.work:work-runtime
Version used: 2.0.0
Devices/Android versions reproduced on: reported on Android 5.0/5.1 (Play Console) / Android 4.4.2/4.4.4/5.0-5.1.1 (Firebase Crashlytics). Multiple devices from various manufacturers, including Samsung, Lenovo, LG, Motorola, HTC, Sony and Asus.

After updating our app from android.arch.work:work-runtime:1.0.0-rc02 to androidx.work:work-runtime:2.0.0, we're seeing crashes when WorkManager starts a job for a significant amount of our users, which doesn't make much sense because the code should be similar to the previous version but it is still a problem.
Unfortunately, we haven't been able to replicate the issue on our 4.4.2 test device. Because the issue is limited to Android versions where JobService isn't used (and the stack trace, see below), it seems like the issue is caused by WorkManager's scheduling and not the job itself.

The worker is set up by a periodic request:

Constraints workerConstraints = new Constraints.Builder().setRequiredNetworkType(NetworkType.CONNECTED).build();
PeriodicWorkRequest userUpdateWorker = new PeriodicWorkRequest.Builder(UserUpdateWorker.class, 8, TimeUnit.HOURS)
.addTag(UserUpdateWorker.class.getName())
.setConstraints(workerConstraints)
.build();
WorkManager.getInstance().enqueue(userUpdateWorker);

Stack trace from the Crashlytics/Play Console crash reports:

Fatal Exception: java.lang.RuntimeException: Error receiving broadcast Intent { act=android.net.conn.CONNECTIVITY_CHANGE flg=0x4000010 (has extras) } in androidx.work.impl.constraints.trackers.NetworkStateTracker$NetworkStateBroadcastReceiver@42849958
at android.app.LoadedApk$ReceiverDispatcher$Args.run (LoadedApk.java:941)
at android.os.Handler.handleCallback (Handler.java:739)
at android.os.Handler.dispatchMessage (Handler.java:95)
at android.os.Looper.loop (Looper.java:145)
at android.app.ActivityThread.main (ActivityThread.java:6117)
at java.lang.reflect.Method.invoke (Method.java)
at java.lang.reflect.Method.invoke (Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1194)
Caused by java.util.concurrent.RejectedExecutionException: Task java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask@2ac263d0 rejected from java.util.concurrent.ScheduledThreadPoolExecutor@320e0fc9[Terminated, pool size = 0, active threads = 0, queued tasks = 0, completed tasks = 0]
at java.util.concurrent.ThreadPoolExecutor$AbortPolicy.rejectedExecution (ThreadPoolExecutor.java:2011)
at java.util.concurrent.ThreadPoolExecutor.reject (ThreadPoolExecutor.java:793)
at java.util.concurrent.ScheduledThreadPoolExecutor.delayedExecute (ScheduledThreadPoolExecutor.java:298)
at java.util.concurrent.ScheduledThreadPoolExecutor.schedule (ScheduledThreadPoolExecutor.java:503)
at java.util.concurrent.Executors$DelegatedScheduledExecutorService.schedule (Executors.java:644)
at androidx.work.impl.background.systemalarm.WorkTimer.startTimer (WorkTimer.java:82)
at androidx.work.impl.background.systemalarm.DelayMetCommandHandler.onAllConstraintsMet (DelayMetCommandHandler.java:100)
at androidx.work.impl.constraints.WorkConstraintsTracker.onConstraintMet (WorkConstraintsTracker.java:150)
at androidx.work.impl.constraints.controllers.ConstraintController.updateCallback (ConstraintController.java:134)
at androidx.work.impl.constraints.controllers.ConstraintController.onConstraintChanged (ConstraintController.java:141)
at androidx.work.impl.constraints.trackers.ConstraintTracker.setState (ConstraintTracker.java:103)
at androidx.work.impl.constraints.trackers.NetworkStateTracker$NetworkStateBroadcastReceiver.onReceive (NetworkStateTracker.java:170)
at android.app.LoadedApk$ReceiverDispatcher$Args.run (LoadedApk.java:931)
at android.os.Handler.handleCallback (Handler.java:739)
at android.os.Handler.dispatchMessage (Handler.java:95)
at android.os.Looper.loop (Looper.java:145)
at android.app.ActivityThread.main (ActivityThread.java:6117)
at java.lang.reflect.Method.invoke (Method.java)
at java.lang.reflect.Method.invoke (Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run (ZygoteInit.java:1399)
at com.android.internal.os.ZygoteInit.main (ZygoteInit.java:1194)