I believe if you wish to go on a Sunday then you definitely need to book. They have two sessions one from 12 pm to 2 pm and then 3 pm to 5 pm.
I believe it would be better to pre book rather than just arrive and be disappointed.
Yes you do and you can do so online. You do not need to prepay and they will sms confirmation to you as well.
During the week, I imagine there may be free tables but not the range of food that is available at weekends.
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