What is the most number of hours that one is allowed to hang around the United Club?

Needed to book travel for a family member at last minute and the only flights available using miles involve a 9-hour layover or an overnight stay. Both are domestic to international connections.

I picked the one with 9-hour layover. She didn't mind(I've seen her play Solitare on her iPad for 4+ hours straight, so I think she'll be fine. I bought a pass so she can sit in United Club for some food and drinks.(was already buying Economy Plus seats and noticed that it was only $23 or $24 extra to add United Club access, so I figured, why not?)

They won't have problem if she spends 8 hours in the club, right?