That was a joke in the release video. The Pythia model is already released at [1] and the deltas for the LLaMa model should be up here [2] in the next few days.
[1] https://huggingface.co/OpenAssistant/oasst-sft-4-pythia-12b-...
[2] https://huggingface.co/OpenAssistant/oasst-llama-based-model...