There's no "reset". There's a 0-100 count with RNG pinking a number in there which is where the Supercontainer will happen. After receiving the Supercontainer you continue until you finish the journey to 100 and being the next journey to 100 with RNG placing a Supercontainer somewhere within there.
I believe it's stated in the Container Description webpage that it refers to Daily Containers (as in, the Containers you could choose for a Daily Reward).
Not "Guaranteed to get a rare ship", it's stating that one of the 3 ship categories will be pulled from.
It means that if no Ship group has been pulled over 165 Supercontainers, the 166th Supercontainer would be guaranteed to pull from 1 of the ship available Ship Groups.
My intention was to say "The Container Types which are available via Daily Tasks". In that sense, Resource/Credit/TryYourLuck/Signal containers can be described as "Daily Containers" as a form of reference/description.
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