I’ve just tried a fresh upgrade from a stock emonSD-07Nov16 and ran into an issue updating Oracle JDK 8.
Preconfiguring packages ...
Setting up oracle-java8-installer (8u144-1~webupd8~0) ...
Using wget settings from /var/cache/oracle-jdk8-installer/wgetrc
Downloading Oracle Java 8...
--2017-10-19 16:10:26-- http://download.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-arm32-vfp-hflt.tar.gz
Resolving download.oracle.com (download.oracle.com)... 104.86.111.155, 104.86.110.251
Connecting to download.oracle.com (download.oracle.com)|104.86.111.155|:80... connected.
HTTP request sent, awaiting response... 302 Moved Temporarily
Location: https://edelivery.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-arm32-vfp-hflt.tar.gz [following]
--2017-10-19 16:10:26-- https://edelivery.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-arm32-vfp-hflt.tar.gz
Resolving edelivery.oracle.com (edelivery.oracle.com)... 104.73.149.93, 2a02:26f0:e8:28a::2d3e, 2a02:26f0:e8:282::2d3e
Connecting to edelivery.oracle.com (edelivery.oracle.com)|104.73.149.93|:443... connected.
HTTP request sent, awaiting response... 302 Moved Temporarily
Location: http://download.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-arm32-vfp-hflt.tar.gz?AuthParam=1508429546_4f5c1524967427ecd613a979707693a8 [following]
--2017-10-19 16:10:26-- http://download.oracle.com/otn-pub/java/jdk/8u144-b01/090f390dda5b47b9b721c7dfaa008135/jdk-8u144-linux-arm32-vfp-hflt.tar.gz?AuthParam=1508429546_4f5c1524967427ecd613a979707693a8
Connecting to download.oracle.com (download.oracle.com)|104.86.111.155|:80... connected.
HTTP request sent, awaiting response... 404 Not Found
2017-10-19 16:10:27 ERROR 404: Not Found.
download failed
Oracle JDK 8 is NOT installed.
dpkg: error processing package oracle-java8-installer (--configure):
subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
oracle-java8-installer
E: Sub-process /usr/bin/dpkg returned an error code (1)
Its seems Oracle are having issues at their end, I don’t think there is much we an do other than wait for them to fix the issue 
Here’s another thread discussing the issue: