Sorry for my English.

I could not identify any pattern, but, for example, i send an items value to zabbix server by zabbix_sender with command:

echo - messages 1540449189 "Неисправность: Модулятор - Требуемый PID не найден." | zabbix_sender -z server_ip -p 10051 -s host_name -T -i -

I use the current value (or old value) of unixtime, all timestamp be in an increasing order.

Often i see the receiving value in the latest data, but I don't see the trigger state change (including for recovery values).