How long can a help desk service request remain in the system?

Summary:

hello,

if I do not set the ORA_SVC_DELETE_CLOSED_SR_ENABLED profile option that allows the automatic deletion of a SR that has been closed for at least the number of days specified by the ORA_SVC_CLOSED_SR_RETENTION_DAYS profile option.
How long will I have access to a service request?
how long will I be able to view that SR or download an attachment in it?
if I don't enable the profile option ORA_SVC_DELETE_CLOSED_SR_ENABLED, and, for example I will going to use the help desk for 20 years, I will still able to search for an SR opened 20 years ago and looking for attachment (for exemple)?