We recommend you split your stay into two separate reservations at different hostels nearby. Usually the hostel's maximum night policy is strict and you wouldn't want to get stuck without a place to stay during your visit!
Otherwise, book the maximum number of nights and then call them directly to see if you can extend your stay further.
Just book a reservation for a few days online and then when you get there talk to the manager. You have more negotiation room for longer stays if you book face to face.
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