https://requests.ci-train.ubuntu.com/static/britney/vivid/landing-010/excuses.html has another current case:

qtmultimedia-opensource-src (5.4.1-1ubuntu19~overlay3~vivid1~test4 to 5.4.1-1ubuntu19~overlay4)
[...]
    autopkgtest for pyqt5 5.4.1+dfsg-2: amd64: Test in progress, armhf: Pass [artifacts], i386: Pass [artifacts], ppc64el: Pass [artifacts]

I checked the worker logs, and the latest request for this came in on April 13 and was run successfully:

2016-04-13 12:33:42,481 INFO:worker Received request for package pyqt5 on vivid/amd64; params: {u'ppas': [u'ci-train-ppa-service/stable-phone-overlay', u'ci-train-ppa-service/landing-010'], u'triggers': [u'qtmultimedia-opensource-src/5.4.1-1ubuntu19~overlay4']}
2016-04-13 12:33:42,710 INFO:worker Running /home/ubuntu/autopkgtest/run-from-checkout --output-dir /tmp/adt-work.2LBsuD/out --timeout-copy=6000 --setup-commands if grep -q trusty /etc/lsb-release; then apt-get install -y build-essential; fi; [ ! -d /usr/share/doc/lxd ] || $(which eatmydata || true) apt-get purge --auto-remove -y lxd; apt-get purge --auto-remove -y ubuntu-snappy-cli || true --setup-commands /home/ubuntu/autopkgtest/setup-commands/setup-testbed --setup-commands apt-key adv --keyserver keyserver.ubuntu.com --recv-key B4C396DF0DD9A0ED00B21D2885504128ECF1204C --setup-commands REL=$(sed -rn "/^(deb|deb-src) .*(ubuntu.com|ftpmaster)/ { s/^[^ ]+ +(\[.*\] *)?[^ ]* +([^ -]+) +.*$/\2/p; q }" /etc/apt/sources.list); echo "deb http://ppa.launchpad.net/ci-train-ppa-service/stable-phone-overlay/ubuntu $REL main" > /etc/apt/sources.list.d/autopkgtest-ci-train-ppa-service-stable-phone-overlay.list; echo "deb-src http://ppa.launchpad.net/ci-train-ppa-service/stable-phone-overlay/ubuntu $REL main" >> /etc/apt/sources.list.d/autopkgtest-ci-train-ppa-service-stable-phone-overlay.list;  --setup-commands apt-key adv --keyserver keyserver.ubuntu.com --recv-key B4C396DF0DD9A0ED00B21D2885504128ECF1204C --setup-commands REL=$(sed -rn "/^(deb|deb-src) .*(ubuntu.com|ftpmaster)/ { s/^[^ ]+ +(\[.*\] *)?[^ ]* +([^ -]+) +.*$/\2/p; q }" /etc/apt/sources.list); echo "deb http://ppa.launchpad.net/ci-train-ppa-service/landing-010/ubuntu $REL main" > /etc/apt/sources.list.d/autopkgtest-ci-train-ppa-service-landing-010.list; echo "deb-src http://ppa.launchpad.net/ci-train-ppa-service/landing-010/ubuntu $REL main" >> /etc/apt/sources.list.d/autopkgtest-ci-train-ppa-service-landing-010.list;  --apt-upgrade pyqt5 --env=ADT_TEST_TRIGGERS=qtmultimedia-opensource-src/5.4.1-1ubuntu19~overlay4 --- ssh -s /home/ubuntu/autopkgtest/ssh-setup/nova -- --flavor autopkgtest --name adt-vivid-amd64-pyqt5-20160413-123342 --image ubuntu/ubuntu-vivid-.*-amd64-server --keyname testbed-juju-prod-ues-proposed-migration-machine-3 --net-id=net_ues_proposed_migration -e 'http_proxy=http://squid.internal:3128' -e 'https_proxy=http://squid.internal:3128' -e 'no_proxy=127.0.0.1,127.0.1.1,localhost,localdomain,novalocal,internal,archive.ubuntu.com,security.ubuntu.com,ddebs.ubuntu.com,ppa.launchpad.net' --mirror=http://ftpmaster.internal/ubuntu
2016-04-13 12:40:46,289 INFO:worker adt-run exited with code 0
2016-04-13 12:40:46,315 INFO:worker Putting results into swift autopkgtest-vivid-ci-train-ppa-service-landing-010 vivid/amd64/p/pyqt5/20160413_124046@

April 13 sounds old, but it matches the timestamps from https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/landing-010/+packages, and the other tests in that PPA were from April 13 as well.

https://objectstorage.prodstack4-5.canonical.com/v1/AUTH_77e2ada1e7a84929a74ba3b87153c0ac/autopkgtest-vivid-ci-train-ppa-service-landing-010/vivid/amd64/p/pyqt5/20160413_124046@/log.gz does have the correct log too.

So this must be some problem on the britney side that misses/ignores this result.