Ours just says "promptly available". The company has attempted to define that as two hours but APA rejected it.

IMO, that means upon being called, you'll stop what you're doing and get ready for work and head in. Resisting the hard timeline is to avoid people feeling they need to do unsafe things to make it to work. Most people live or have crashpads within an hour or two of a base so it's typically not an issue.