Hi. I still desagree. If the appending of the history is ot correct as you argue then everything also in this post is wrong : https://machinelearningmastery.com/how-to-develop-deep-learning-models-for-univariate-time-series-forecasting/?fbclid=IwAR2aJtxyn6oulHpRY4eotqaRFOb3NHukmBT46R6IFPDBdpiHaoX9J3xflFA

i do not think this is the case.