The expiryTime passed in the SSO token is the expiry time of the token. This implies that the token will be valid for the time period specified. You can sign in again using the same token even if you are logged out of the application if the token is still valid.
The default session timeout for Helical Insight application is 30 minutes. Hence, the user is logged out if the application is idle for 30 minutes. When you generate a token with expiryTime of 24 hours, you can login to Helical Insight using the same token within the 24 hours time period.
You can modify the session timeout of Helical Insight
and keep it greater than or equal to the expiry time of the SSO token in order that the session remains running till the SSO token is valid. In this case, modify the session timeout to 24 hours or greater. Then the user will not be logged out of Helical Insight application unless the SSO token expires (in 24 hours).