I ran sudo git -C /var/www/emoncms fetch --all --prune -v
Then sudo git -C /var/www/emoncms describe --tags --debug

Looks good now:

pi@emonpi:~ $ sudo git -C /var/www/emoncms describe --tags --debug
searching to describe HEAD
 annotated          4 9.9.8
 annotated          9 9.9.7
 lightweight       41 9.9.6
 lightweight      229 9.9.5
 lightweight      243 9.9.3
 annotated        246 9.9.4
 lightweight      297 V9.9.2
 lightweight      300 v9.9.1
 lightweight      305 v9.9.0
 lightweight      756 9.8.31
traversed 839 commits
more than 10 tags found; listed 10 most recent
gave up search at 50c7901bca2ffd2226798bbca8a6bcc78c48f94b
9.9.8-4-gd0db7a57
pi@emonpi:~ $

also…

pi@emonpi: ~ $ sudo git -C /var/www/emoncms describe

9.9.8-4-gd0db7a57

pi@emonpi: ~ $