can there be any problem due to rains .. as this is monsoon season ? do they carry out tours in rains ?
As others have already answered, it is best asked directly to the tour operator.
Generally the best time to visit Sunderbans would be from September/October to March.
However that said, tour operators would understandably pitch for tours such as "Sunderbans in the rains" etc. :)
Gut feeling yes. I would recommend you to get on hand advice from the agency directly
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