A delayed-start expiry is stored as a negative duration, but the card checked
the disabled-client branch before the sign of that duration, so it printed the
epoch position (-2592000000 ms -> 1969-12-02) and labelled it an expire date.
The sign decides first now, which is how BuildClientDraftMessage in this file,
subscriptionExpiryFromClient and adjustTraffics already read the same value; the
Discord card is the one surface still reading it as unlimited, fixed in #6498.
BlindMaster24