We currently use eviews for our forecasts. Our models tend to perform OK over a longer timeframe but perform dreadfully in the shorter term. Typically, we will overwrite these numbers to adjust the forecast. It is straightforward in eviews. Before you solve the model, you change the residuals in the forecast period. This has the suffix "_a".
Is there an equivalent way to amend or overwrite periods of forecasts using R instead of eviews?
I understand it could be package-specific, so I will mostly be using the ARDL or forecast package.