The dependencies in Alphas are currently >= 2.0.0 and should be >=2.0.0a0 in order to work with Alphas in cases which are not PEP 440-compliant.

According to https://www.python.org/dev/peps/pep-0440/, >= 2.0.0 should also work with alpha/beta releases (a1/a2) but in some cases it does not (https://apache-airflow.slack.com/archives/C0146STM600/p1602774750041800) 

Changing to ">=2.0.0a0" should help.
provider_packages/setup_provider_packages.py
else:
                last_commit_hash = found.group(1)
                release_version = file_name[len(changes_file_prefix):][:-3]
                release_version_no_leading_zeros = strip_leading_zeros_in_calver(release_version) \
                    if backport_packages else release_version
                past_releases.append(
                    ReleaseInfo(release_version=release_version,
                                release_version_no_leading_zeros=release_version_no_leading_zeros,
                                last_commit_hash=last_commit_hash,
                                content=content,
                                file_name=file_name))
    return past_releases
def get_latest_release(provider_package_path: str, backport_packages: bool) -> ReleaseInfo:
    """
    Gets information about the latest release.
    :param provider_package_path: path of package
    :param backport_packages: whether to prepare regular (False) or backport (True) packages
    :return: latest release information
    """
    releases = get_all_releases(provider_package_path=provider_package_path,
                                backport_packages=backport_packages)
    if len(releases) == 0:
        return ReleaseInfo(release_version="0.0.0",
                           release_version_no_leading_zeros="0.0.0",
                           last_commit_hash="no_hash",
                           content="empty",
                           file_name="no_file")
    else:
        return releases[0]
def get_previous_release_info(previous_release_version: str,