I have noted that every time that my ISP resets my PPPoE connection, all my ZT interfaces stops passing traffic. No errors shown anyway, it silent stop working.
The only way to restore it is manually disabling and enabling the zt1 instance.
This happens on every 7.2rc and may also affect the 7.2 stable, as I did not saw any mention of it on changelog and my Support ticket is untouched and unanswered by a month.
one important info, this doesn't seem to happen if I terminate the connection on my side, only when the ISP does.