Is it the type of rain that gradually increases starting in November, or is it a dry season followed by more of an immediate downpour?

I am trying to figure out if they will be able to test Owen before the site becomes unreachable and I think the nature of the wet season would be key to that.

Does anyone know when in the past (ie, end of November) Central, Baraka or any of the other companies in the area usually stop working on location?