AC wants all page-ranges to be shown in their entirety, so I ran some XQuery to generate fixes for the abbreviated ones:

let $commands :=
for $p in //table_data[@name='poems']/row
return
let $pages := $p/field[@name='po_pages']/text(),
$id := $p/field[@name='po_id']/text()
return
if (matches($pages, '^\d\d\d-\d\d$')) then
concat('UPDATE `poems` set `po_pages` = "', substring($pages, 1, 4), substring($pages, 1, 1), substring($pages, 5), '" WHERE `po_id` = "', $id, '";')
else 
if (matches($pages, '^\d\d-\d$')) then
concat('UPDATE `poems` set `po_pages` = "', substring($pages, 1, 3), substring($pages, 1, 1), substring($pages, 4), '" WHERE `po_id` = "', $id, '";')
else ()
return string-join($commands, '
')

then ran the commands (after testing in dev) to fix the existing problems. Added a new test to the diagnostics for this.