Why I cannot access the most recent data?
Because of the agreed data policy with the data providers, the S2S realtime type of forecast can be accessed only with 3 weeks delay. There should not be any such restriction for the reforecasts.
What are reforecasts?
Reforecasts are forecasts run using the same model version as real-time forecast for a number of past dates. More details here.
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In order to retrieve data efficiently users should follow instructions about S2S reforecasts retrieval efficiency.
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Do you have any examples of S2S data retrieval scripts?
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