For a Lifecycle that is used by a Channel of a Project and not assigned as default Lifecycle of a Project, the Project is not listed as using the Lifecycle in the Lifecycle details.
Hi,
Thanks for getting in touch! I have just tested this on my machine using Octopus version 3.11.1. Would you be able to let me know what version of Octopus you are currently using? Also, have you created a release with that project?
Looking forward to hearing from you.
Best regards,
Daniel
We are using 3.3.12, of course many releases.
Roberto
Hi Roberto,
Thanks for getting back with that! I apologies for not noticing that you had your version in the title of your question. I had a chat to the devs and it looks like there is a GitHub issue for this issue. I have added this ticket as a source to the issue. You can track the progress of the issue here:
Hope that helps. 
Best regards,
Daniel
We have upgraded to the latest version and the issue has been resolved, thanks.