If your flight arrives at a time when your hotel does not allow check-in, there are a few options you can consider:

1. Consider booking a hotel room for the previous night so that you can check in as soon as you arrive. This may be more expensive, but it can be a good option if you are very tired and want to get some rest right away.

2. Ask the hotel if they can make an exception and allow you to check in early. Some hotels may be able to accommodate early check-ins if they have availability, although there may be an additional fee for this service.

3. Consider booking a hotel room that offers a luggage storage service. This way, you can drop off your luggage and explore the city while you wait for your room to be ready.

4. Look for a hotel with a 24-hour front desk or lobby area where you can rest and relax until your room is ready. Some hotels may also have a lounge area where you can sit and wait.

5. If none of these options are available or feasible, you may need to find a place to pass the time until your room is ready. This could include finding a coffee shop or restaurant to sit in, or visiting a local attraction.

It's always a good idea to plan ahead and consider these options when booking a hotel, especially if you are arriving very early in the morning or late at night.