Learn English – Alternative phrase for “Service user”

I am looking for a phrase to replace the term "Service user". There are two different contexts.

1. Someone receiving services from a mental health trust.
2. Someone who received services in the past, or who is receiving services now, or who will be using services in the near future, and who is offering their expertise to help develop services.

Here are some words, and the problems that have been mentioned.

For 1:

"Patient" – A patient receives medical services. These people receive more than just medical services; they get vocational services and social care and etc.

"Service user" – Some people (a few people with drug and alcohol problems for example) do not like the word "user".

"Client" – People detained against their will under section of the Mental Health Act say they don't feel like clients.

At the moment the term used is "service user". Only a small number of people dislike the word, but their dislike is very strong, so an alternative would be good.

For 2: We need a word that highlights the new role; a word that avoids "pigeon holing" people. We'd really like a phrase that puts people on a more equal footing with their employed colleagues.

"Service user" – these people might not be service users any more. They are moving forward with their lives, and want to define a more positive role for themselves. Also we'd like to emphasise the expertise that these people bring.

"Expert by lived experience" – It's unwieldy. Many people dislike the "lived experience" bit. A few people have said that they do not feel like experts.

"Service reporter" – sometimes these people are not reporting their experiences. They're just using their experience to help. For example, as part of an interview panel.

"Service consultant" – consultant is problematic in the setting of a hospital. There are actual medical consultants (US equivalent: "Attending Physician"). A small number of people are uncomfortable with the word "consultant". They say it has negative connotations; they say it makes them think of someone getting paid a lot of money for providing little value.

I welcome all suggestions. They don't have to be in use anywhere in the world. You can create brand new terms. I'm happy to hear what terms are used in other places too.