Force random delay to update interval

[MathieuMD]

Hello,

Zabbix v6.0.21 on Ubuntu 22.04

I have a template (linked to 30 hosts) with an "HTTP Agent" item daily requesting an URL from a public website. I need all that 30 checks to be spread on several hours, because the website have a quota of 10 requests per hour max.

If I set the "Update interval" to "1d", all 30 checks are done almost at the same time (only a few minutes apart), and the website will therefore allow 10 firsts, and drop 20 others!

I tried to set "Update interval" to a macro defined in the template, `{$RANDOM_DELAY}`. I tried all these values: `{24*3600 + rand(0, 6*3600)}` (hoping it would limit the random range from 0 to 6*3600), `{24*3600 + rand()}` and even `{rand()}`, but all got "Invalid update interval".

I also hoped to use Preprocessing JavaScript, but preprocessing is executed *after* data gathering, so it cannot help me.

So I have two questions:
1. Is there a way to delay data gathering at the item definition?
2. Optionally, is there no way to limit rand() returned range? (like PHP's rand())

Thanks for any idea!