502 Bad Gateway on Frontend After Update to beta 3 (from 2)

Drupal Version: 10.4.7

Domain module version: 2.20.0-beta 3

We are encountering 502 Bad Gateway errors on all front end pages of our site following a rebuild of our composer.lock file witch auto upgraded the Domain module from 2.0.0-beta2 to 2.0.0-beta3. I suspect it has something to do with our hosting platform set up for Edge/Varnish (on Acquia) as it works find in my simple local dev environment.

The issue only affects the front end of the site; the Drupal admin area is fully functional.

Steps Taken So Far:

• Verified domain records in Domain Access are valid.
• Cleared Drupal cache (drush cr).
• Cleared Acquia Varnish cache.
• Verified domains are properly listed in Acquia Cloud UI.
• Confirmed settings.php trusted host patterns are correct.
• No circular redirects are present (curl -I -L confirms).
• Logs show 502s but no PHP errors related to Domain Access.

Symptoms:

• Admin pages (/admin/*) load fine.
• Any content routed through Domain Access on the frontend returns 502.
• 502 is consistent across all affected domains.
• Same site codebase works without issue outside of Acquia.

Any thoughts on where to start debugging would we greatly appreciated. I've included all i see in the various logs below.

thanks,
summer

drupal-request srv-6776 [25/Jul/2025:22:55:36 +0000] support-stage.foresightsports.com GET /support http_code=200 query= uid=1 php_pid=26443 php_time=0.238 queue_wait=0 request_id="v-7a326146-69aa-11f0-9ae1-27b5762bee0e" drupal_version="10.4.7"
drupal-request srv-6776 [25/Jul/2025:22:55:36 +0000] support-stage.foresightsports.com GET /support http_code=200 query= uid=1 php_pid=26443 php_time=0.238 queue_wait=0 request_id="v-7a326146-69aa-11f0-9ae1-27b5762bee0e" drupal_version="10.4.7"
apache-request srv-6776 98.176.50.241 - - [25/Jul/2025:22:55:36 +0000] "GET /support HTTP/1.1" 103 6181 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.0" vhost=foresightsportswmybz9vtih.devcloud.acquia-sites.com host=support-stage.foresightsports.com hosting_site=foresightsportswmybz9vtih pid=12173 request_time=260768 forwarded_for="98.176.50.241" request_id="v-7a326146-69aa-11f0-9ae1-27b5762bee0e" location="-"
varnish-request bal-6155 {"time": "[25/Jul/2025:22:55:36 +0000]", "status": "502", "bytes": "150", "method": "GET", "host": "support-stage.foresightsports.com", "url": "/support", "query": "", "referrer": "-", "user_agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.0", "client_ip": "98.176.50.241", "time_firstbyte": "0.241351", "hitmiss": "miss", "handling": "pass", "forwarded_for": "98.176.50.241", "request_id": "v-7a326146-69aa-11f0-9ae1-27b5762bee0e", "ah_log": "", "ah_application_id": "", "ah_environment": "", "ah_trace_id": ""}
bal-request bal-6155 127.0.0.1 - - [25/Jul/2025:22:55:36 +0000] "GET /support HTTP/1.1" 502 300 "-" "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:140.0) Gecko/20100101 Firefox/140.0" status=502 bytes=300 http_host=support-stage.foresightsports.com affinity="-" upstream_addr="10.0.3.123:80" hosting_site=foresightsportswmybz9vtih request_time=0.241 forwarded_for="98.176.50.241" upstream_status="502" request_id="v-7a326146-69aa-11f0-9ae1-27b5762bee0e" ssl_protocol="-" ssl_cipher="-"