Basecamp 5 & Sub-Tasks

[kingxl10]

Hello,

I've just started using the CLI and attempted to use Claude Code to create tasks with sub-tasks, but it gave the following message.

The nested todos (subtask) API returns 404 for this account — Basecamp 3 doesn't support it here. I'll create the review todos as separate items in the same list, which is the closest available option. Let me create all remaining todos now in parallel batches.

I assume that this is because the CLI is only set up for Base Camp 3. Is there a status for when Base Camp 5 features will be available and when subtasks will be available through the CLI?