During my pre-transplant period, while on the waiting list for a liver due to PSC, I was 'temporarily inactivated' when my blood lab results indicated possible cholangiocarcinoma. This required me to be inactivated until a biopsy could be performed and resulted in an "all clear" diagnosis. I would then be re-activated on the transplant waiting list.

@rodney9999, @contentandwell
Here is the definition of Active Candidate from the Organ Procurement and Transplantation Network>Glossary https://optn.transplant.hrsa.gov/resources/glossary/
"A transplant candidate eligible to be considered for organ offers at a given point in time. Some transplant candidates are temporarily classified as “inactive” by their transplant center because they are medically unsuitable for transplantation or need to complete other eligibility requirements."

Rodney9999, this is an excellent question and this is the perfect place to post it. I hope the definition is helpful to you. There is probably no way of knowing what might lead to someone being inactivated, and for how long. But it does happen, and when a person is reactivated, they return to their 'place' as far as ranking by time already spent on the list. This was all new to me when it happened, I guess you can say that I learned by experience.
It is good to hear your voice! How are you getting along?