diff --git a/README.md b/README.md
index 2c85482..3449e28 100644
--- a/README.md
+++ b/README.md
@@ -60,12 +60,12 @@ The main Docker repo URL, common between Debian and RHEL systems.
     docker_apt_repository: "deb [arch={{ docker_apt_arch }}] {{ docker_repo_url }}/{{ ansible_distribution | lower }} {{ ansible_distribution_release }} {{ docker_apt_release_channel }}"
     docker_apt_ignore_key_error: True
     docker_apt_gpg_key: "{{ docker_repo_url }}/{{ ansible_distribution | lower }}/gpg"
-    docker_apt_filename: ""
+    docker_apt_filename: "docker"
 
 (Used only for Debian/Ubuntu.) You can switch the channel to `nightly` if you want to use the Nightly release.
 
 You can change `docker_apt_gpg_key` to a different url if you are behind a firewall or provide a trustworthy mirror.
-Usually in combination with changing `docker_apt_repository` as well.
+Usually in combination with changing `docker_apt_repository` as well. `docker_apt_filename` controls the name of the source list file created in `sources.list.d`. If you are upgrading from an older (<7.0.0) version of this role, you should change this to the name of the existing file (e.g. `download_docker_com_linux_debian` on Debian) to avoid conflicting lists.
 
     docker_yum_repo_url: "{{ docker_repo_url }}/{{ (ansible_distribution == 'Fedora') | ternary('fedora','centos') }}/docker-{{ docker_edition }}.repo"docker_edition }}.repo
     docker_yum_repo_enable_nightly: '0'
diff --git a/defaults/main.yml b/defaults/main.yml
index f0caab8..75a1caf 100644
--- a/defaults/main.yml
+++ b/defaults/main.yml
@@ -40,7 +40,7 @@ docker_apt_ansible_distribution: "{{ 'ubuntu' if ansible_facts.distribution in [
 docker_apt_arch: "{{ 'arm64' if ansible_facts.architecture == 'aarch64' else 'amd64' }}"
 docker_apt_repository: "deb [arch={{ docker_apt_arch }} signed-by=/etc/apt/trusted.gpg.d/docker.asc] {{ docker_repo_url }}/{{ ansible_facts.distribution | lower }} {{ ansible_facts.distribution_release }} {{ docker_apt_release_channel }}"
 docker_apt_ignore_key_error: true
-docker_apt_gpg_key: "{{ docker_repo_url }}/{{ ansible_facts.distribution | lower }}/gpg"
+docker_apt_gpg_key: "{{ docker_repo_url }}/{{ docker_apt_ansible_distribution | lower }}/gpg"
 docker_apt_gpg_key_checksum: "sha256:1500c1f56fa9e26b9b8f42452a553675796ade0807cdce11975eb98170b3a570"
 docker_apt_filename: "docker"