Anthropic's[1][5] post is dated "Mar 13, 2024": "Today we're releasing Claude[2] 3 Haiku ... The model is now available alongside Sonnet and Opus in the Claude API and on claude.ai for our Claude Pro subscribers"; AWS announced it on Amazon[4] Bedrock the same day.
Anthropic releases Claude 3 Haiku, the fastest and cheapest Claude 3 model at $0.25 per million input tokens, able to read about 30 pages of text per second, nine days after announcing it with Opus and Sonnet.