If you're looking for official documents on methodologies used in Refinitiv services, the best self-help resource is MyRefinitiv. If you cannot find what you're looking for on MyRefinitiv, then I would suggest contacting Refinitiv Helpdesk (which you can do by following Get Support prompts on MyRefinitiv).
Is there a context to your question? Does it pertain to a specific product or service? Refinitiv products should be following the market convention in determining the spot date for a currency pair.
This forum is dedicated to software developers using Refinitiv APIs. For any other enquiries, please contact Refinitiv Helpdesk. If your question is related to a Refinitiv API, would you mind specifying which API you're using? If it's not related to Refinitiv APIs, then please contact the Helpdesk.