Steps to reproduce:

1. Create disk discovery with flexible type, intervale 0 and period 1-7,01:00-07:00.
   Probably time can be what ever you wan't to exclude here.
   
2. When you check proxy graph queue over 10 minutes and time is on that exclude. Then this dicovery is calculated inside this count in proxy graph, But it should be like this.

Result:
If you have lot of windows agents then this can couse night time triggered alarms: "Zabbix proxy: More than 100 items having missing data for more than 10 minutes"
Expected:
Using excluded time interval should be counted in for proxy queue item count.