I usually would let my hams out for 30-60 minutes once their confidence was up. At first though, I limited play time to 15 minutes. It’s better to start slow anyway so as to allow them to get used to long periods of time without water, a litter tray, or a secure nesting place. If you notice her mostly hiding, or appearing stressed- it may be time to put her back. However, if she seems happy, I would let her have as much time as she’d like
I’d say you’re fine to increase her play time to 15-20 minutes as you see fit.
Best wishes!