With a minimal build.boot file:
(set-env! :dependencies '[[com.gfredericks/test.chuck "0.2.7" :scope "test"]])
boot show -u suggests [com.gfredericks/test.chuck "0.2.6" :scope "test"].
I expect it to be silent as 0.2.7 is the latest release.
Result of boot --version
#http://boot-clj.com
#Fri Feb 03 15:53:04 CST 2017
BOOT_CLOJURE_NAME=org.clojure/clojure
BOOT_CLOJURE_VERSION=1.8.0
BOOT_VERSION=2.7.1