1. remove fwupd and related deb.
2. Turn on the proposed channel.
3. Then apt-get installs fwupd (1.7.5-3~20.04.1). fwupd-unsigned is not installed, fwupd-signed (1.27.1ubuntu7) is installed properly.
4. "fwupdmgr reinstall" and choose machine bios, as secure boot is off, this works perfectly.
test on focal:
1. remove fwupd and related deb.
2. Turn on the proposed channel.
3. Then apt-get installs fwupd (1.7.5-3~20.04.1). fwupd-unsigned is not installed, fwupd-signed (1.27.1ubuntu7) is installed properly.
4. "fwupdmgr reinstall" and choose machine bios, as secure boot is off, this works perfectly.
Given above, mark verification done for focal.