Attempt to configure proxy.config.admin.user_id with username of length longer than 8 characters causes TS to fail at startup. TS fails attempting to change uid using the first 8 characters of the username.
E.g. (from records.config):
CONFIG proxy.config.admin.user_id STRING bandersnatch
TS fails with message:
FATAL: Can't find entry in password file for user: bandersn