With POST /source-materials, you can now make 60 requests per minute instead of 10; POST /source-materials/{id}/slice now allows 20 instead of 5. Both limits remain per user, and the current values appear in the Rate limit section on each endpoint's reference page.
If you were pacing uploads to stay under the old ceiling, you can let them run faster. Exceeding a limit still returns 429 with a Retry-After header. The uploading files guide explains how to upload a local file and use its public URL with the API.