On August 1, 2017, the S1, S2, and S3 performance levels in DocumentDB will be retired. You can continue using these performance levels through the Azure portal or APIs until August 1, 2017. Beyond that date, each collection that used the S1, S2, and S3 performance levels will be migrated to a single partition collection with equivalent throughput, without any downtime. Post-migration, web-direct customers will pay single partition collection prices. EA customers will not experience a price increase as a result of this migration through the end of their current EA contract. Beyond the current contract, EA customers will pay single partition collection prices.
Why are the S1, S2, and S3 performance levels being retired?
The S1, S2, and S3 performance levels do not offer the flexibility that DocumentDB single partition collections offers. With the S1, S2, S3 performance levels, both the throughput and storage capacity were pre-set. DocumentDB now offers the ability to customize your throughput and storage, offering you much more flexibility in your ability to scale as your needs change.