Windows jobs not running concurrently

In our build we have a matrix that expands out to building our client for OSX, Linux and Windows. Our subscription allows for 5 concurrent build jobs. When we queue a new build, the OSX and Linux builds run concurrent with each other, while the Windows build queues until they are complete. Is this a known issue with Windows builds?

yaml follows.

matrix:
  fast_finish: true
  include:
  - os: osx
    osx_image: xcode11.2
    language: node_js
    node_js: '12'
  - os: linux
    dist: bionic
    node_js: '12'
    language: node_js
  - os: windows
    node_js: '12'
    language: node_js
    env: YARN_GPG=no
cache: yarn
before_install:
- mkdir ~/private_keys
- openssl aes-256-cbc -K $encrypted_c8bd0347fe1a_key -iv $encrypted_c8bd0347fe1a_iv
  -in ./secrets/here-int-gcs-release-key.json.enc -out ./here-int-gcs-release-key.json
  -d
- openssl aes-256-cbc -K $encrypted_c8bd0347fe1a_key -iv $encrypted_c8bd0347fe1a_iv
  -in ./secrets/AuthKey_LCQ3C69862.p8.enc -out ~/private_keys/AuthKey_LCQ3C69862.p8
  -d
- openssl aes-256-cbc -K $encrypted_c8bd0347fe1a_key -iv $encrypted_c8bd0347fe1a_iv
  -in ./secrets/.env-here-int.json.enc -out ./firebase/.env-here-int.json -d
- openssl aes-256-cbc -K $encrypted_c8bd0347fe1a_key -iv $encrypted_c8bd0347fe1a_iv
  -in ./secrets/AuthKey_LCQ3C69862.p8.enc -out ~/private_keys/AuthKey_LCQ3C69862.p8
  -d
- if [ "$TRAVIS_OS_NAME" == "linux" ]; then sudo apt-get -y install libxtst-dev; fi
- npm install -g yarn
before_script:
- if [ "$TRAVIS_OS_NAME" = osx ]; then chmod +x scripts/add-osx-cert.sh; fi
- if [ "$TRAVIS_OS_NAME" = osx ]; then ./scripts/add-osx-cert.sh; fi
script:
- yarn install
- yarn build
- yarn test --ci
- cd electron
- yarn install
- yarn build
- yarn dist:$TRAVIS_OS_NAME
- cd ..
deploy:
- provider: script
  edge: true
  script: bash scripts/deploy.sh
  on:
    branch: master

Please email us at support@travis-ci.com with details (your build log URL, the date and time you observed the phenomenon, etc.) and we’d be happy to look into it.