Add-on 9 of Season 2 download stops under CGNAT – possible DoT (853) DNS failure

Issue:

After reinstalling "Battlefield 6 Season 2", the Base component installed successfully and the game launched. However, the installation of Add-on 9 components stopped during download.

I am sharing this because many players may be using similar Wi-Fi / CGNAT (Carrier Grade NAT) environments.

My environment:

⦁    ISP: UQ WiMAX, Japan (CGNAT environment)
⦁    Router: Speed Wi-Fi Home 5G L13 (ZTE)
⦁    Windows 10 Home
⦁    IPv6 enabled (IPv4 preferred)
⦁    DNS set to automatic in Windows
⦁    Portmaster Secure DNS 9.9.9.11 enabled
⦁    Current download speed: 8 –30 Mbps (2 –4 MB/s), depending on time of day.

Investigation tools:

⦁    Portmaster logs
⦁    TcpView64 (Sysinternals)
⦁    Manual IP confirmation via Command Prompt

Preliminary conclusion:

The issue does NOT appear to be Quad9 (9.9.9.11) itself. Instead, under CGNAT routing, DNS over TLS (port 853) connections intermittently failed.

This caused DNS resolution failure for CDN endpoints (for example, Akamai), which then led to the Add-on download stopping. Under CGNAT, port restrictions or session handling may cause instability.

EA appears to use multiple CDNs such as Amazon Web Services, Akamai, Cloudflare, and Fastly. I will monitor stability and download speed during the next EA update.

If anyone else is using CGNAT (mobile/home 5G Wi-Fi) and experienced Add-on download interruptions, I would appreciate your feedback.