🐛 [BUG] - Notification rule with 5s window fires every ~7s instead of 5s (Fledge v3.1.0)

[AshishAvesta]

Description

While testing the notification service with a Modbus simulator, I observed that notifications are not triggered at the expected 5s interval when using a window evaluation.

I have attached screenshots of the south service configuration (Modbus coil setup) and the notification configuration (rule + delivery settings) for reference.

Environment Platform

• Fledge version: 3.1.0 - South service: Modbus - notification delivery: MQTT (but the issue is visible in notification logs regardless)

Fledge Version

3.1.0

Installation

Source Code

Steps To Reproduce

1. Create a south Modbus service with a coil (active) = 1.

2. Configure a notification service:

     - Type: Retriggered
     - Retrigger time: 5s (also tested with 0s)

3. Configure Rule:

     - Data evaluation type: Window
     - Window size: 5s
     - Window evaluation: Maximum

4. Observe notification logs.

Expected Behavior

• With Window = 5s, the notification should be evaluated and fired every ~5s (or at least closer to 5s).
• With Retrigger = 0, I expected immediate re-firing after each window evaluation, still aligned to ~5s.

Screenshots

Logs

Support bundle

support-250813-04-25-11.tar.gz