If you don't care about being more update to date than the maintainer just follow the ChangeLog.
I do something similar to this:
#Log the date you checked for updates.
head -"$(grep -n '$dateoflastupdate' ChangeLog.txt)" | while read entry ; do sbname=`echo $entry | cut -d: -f1 | cut -d/ -f2` && if [ -n "$(ls /var/log/packages | grep $sbname)" ]; then echo $entry ;fi ;done
It should produce all the info you need when considering an update. just wget the scripts. resolve sources, build and upgrade.
*probably made an error since im on a phone and writing off the top of my head, nevertheless too tedius to double check.. You got the jist I hope