Perhaps https://aws.amazon.com/sagemaker/data-labeling/ ? Source: almost 2 years ago

In this session you will discover how to use Amazon SageMaker to prepare data for machine learning in minutes. SageMaker provides data preparation tools that make it easier to label, prepare, and analyse your data. Walk through a complete data-preparation workflow, including how to use SageMaker Ground Truth to label training datasets, as well as how to extract data from numerous data sources, convert it using... - Source: dev.to / over 2 years ago

As for who run MLD I guess It’s Amazon itself, have a look at this https://aws.amazon.com/sagemaker/groundtruth/. I speculate that multiple companies use this resource and they are the one responsible to upload the correct instructions, Amazon just redirect the labeling job for us using and requester account in mTurk, that explains why the communication is unacceptable with this requester. Source: over 2 years ago

Unless you are provisioning instances in a development account, always plan the instance count required, pay upfront, and leverage the many cloud savings plans at your disposal ( AWS Savings plans, Azure’s Cost Management and GCPs committed use discounts). Many cloud providers have different ways of leveraging the excess compute power they have by buying time on spot and reserved instances. - Source: dev.to / over 1 year ago