Do I have to call Yancy/Curtis 50 times all in one day, or can I take an infinite number of days?

Question

Stupid sidequest....
I just wanted a freakin Snorlax...

Answer 1

First pf all, you do not have to call them 50 times to trade. You can trade with them after the 30th call.
Secondly, you can take as many days as you want to make the thirty calls. You can call them more than once a day, but you can only trade with them once a day.
In short, you don't need to make every call in one day and you can trade after 30th call (if you have beaten the Elite Four).
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Answer 2

After returning his Xtransceiver, the game will randomly select one of the 15 areas where Curtis called the player initially, and the player can call Curtis from anywhere in that area. This will happen every time Curtis is called from then on. After the thirtieth call, the player may join Curtis in a ride at the Rondez-View Ferris Wheel. After the first call of every next day, Curtis will ask the player for a Ferris Wheel ride, and if the player has entered the Hall of Fame, he will offer to trade a Pokémon after the ride.

To trade with Yancy/Curtis, you need 30 calls total, and need to have entered the Hall of Fame. The calls do not need to be made in succession or through separate days; just total. You can only trade once per day.

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