What this line in DSDPLUS mean ?

Hi
I got this line in DSDPLUS
Emerg Enc Bcast OVCM Private call TGT = 23 src-55 slot =2s

What does it mean ? what is OVCM ? and why the slot is in seconds and not 1 or 2 ?
any clarification welcome
Thanks Forward
Ronen - 4Z4ZQ
hrrp://www.ronen.org

OVCM- Open Voice Channel Mode, allows third party users to monitor

Any time I saw Enc OVCM in the DSD event log it was just a bunk decode as it was a normal clear voice call.

Thank you for the info
so in that case that mean that a radio with every TG will hear this announcement ?
so why it is written as private call ?
and why the slot is in seconds and not 1 or 2 and what is the real slot that the announcement is on ?
Thanks Forward
Ronen- 4Z4ZQ
Ronen Pinchooks (4Z4ZQ) WebSite