I am unable to find any documentation on the convention for offsetting when using the API Search function, which appears to have a limit of 10,000 on itemsToReturn. The most suitable approach appears to be offsetting by an additional 10,000 every iteration until all objects have been searched.
Assistance would be much appreciated with identifying:
a) the conventions for iterating an additional 10,000 item offset; and
b) how to calculate the total count of the objects the API needs to search.