[Bug]: MAX_RETRANSMIT false positives with router_late broadcast window

[mdecourcy]

Category

Other

Hardware

Not Applicable

Is this bug report about any UI component firmware like InkHUD or Meshtatic UI (MUI)?

• Meshtastic UI aka MUI colorTFT
• InkHUD ePaper
• OLED slide UI on any display

Firmware Version

2.7.17.78baaf448 (dev build)

Description

Problem:
Firmware sends MAX_RETRANSMIT errors even when ROUTER_LATE nodes successfully rebroadcast messages, because the implicit ACK timeout expires before ROUTER_LATE nodes transmit.

Cause:

• ROUTER_LATE can delay up to ~7,000ms
• Sender's retransmission timeout: ~5,000-6,000ms
• ROUTER_LATE rebroadcast arrives AFTER sender has already retransmitted

Expected:
The retransmission timeout should be longer than the maximum ROUTER_LATE delay, or ROUTER_LATE rebroadcasts should not be expected to generate implicit ACKs. This should happen ideally before #8567 goes to alpha

Actual behavior:
Most to all messages sent from nodes I have downstairs are hitting MAX_RETRANSMIT even though they are successfully being broadcasted by my upstairs CLIENT_BASE on 2.7.17.78baaf448 (dev build)

Relevant log output

[github-actions]

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