i've discovered a bit late - a series of patches to fix issues for the 'ajax circ' feature (BZ11703) in 3.16
http://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=11703
specifically, these patches...
730f416 Bug 13537 - Focus should move to barcode after renewing via checkouts table
2d70457 Bug 13290 - Add better feedback for returns to the checkouts table
7477cbc Bug 13408: Tell librarians they may continue scanning while checkouts table is loading
24a749d Bug 13293 - Regression: Override renewal limit option broken with AJAX circ
6e20fdf Bug 13286 - Checkouts table due date not updated when an item is renewed.
13fda83 Bug 13195 - Regression: Circulation checkouts table no longer shows item type description
48db11d Bug 13236 - Regression: Table of checkouts no longer preselects overdue items for rewewal
17e6a8b Bug 12778 - Regression: Item lost status doesn't show in list of checkouts
dd385fc Bug 13253 - Unnecessary white space above checkouts table in circulation
8848e72 Bug 13020 - Checkouts table default ordering is incorrect
d8ed913 Bug 12899: Row grouping in checkouts table is alphabetical and depends on translation
b8fae84 Bug 12729 - Overdue items won't show as overdue in red in circulation
most of these patches don't apply clean, and need to be manually added to 3.16 (which is also risky and fiddly)
because these patches are (imho) the most urgent for 3.16 - i plan to reset the 3.16.x branch back to the 'v3.16.6 tag', then add these corrected patches 1st, before less urgent patches
6971b7d532