Since you don't have launch_type set, you shouldn't be setting platform_version:
Platform version on which to run your service. Only applicable for launch_type set to FARGATE. Defaults to LATEST. More information about Fargate platform versions can be found in the AWS ECS User Guide.
@dry-keyboard-94795 thanks for sharing these doc details, will take a look later.
I decided to simply keep the platform arch to x86_64 for now, which is the default.
Although I think graviton is suppose to be a much more efficient cpu arch.
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