Could be related to #2.

Camera configuration:

CameraConfiguration.cameraConfiguration()
                .width(1920)
                .height(1080)
                .automaticWhiteBalance(AutomaticWhiteBalanceMode.AUTO)
                .exposureMode(ExposureMode.AUTO)
                .exposureMeteringMode(ExposureMeteringMode.MATRIX)
                .encoding(Encoding.JPEG)
                .quality(85)

Happens rarely but more than once per day if taking photos constantly.
Hardware: Raspberry Pi 2B, revision a01041, Pi Camera rev v1.3.
Software: Raspbian 9.6, fresh install with all updates.

Restarting application helps.
Waiting does not help (tested > 1h).
Calling close does not help.
Requesting one more image on different thread does not help.

Trace logs attached, around timestamp 741834 library did not return image.
timelapse_logs.txt