Walk-Forward Tradable Coverage 1

A rolling walk-forward scheme uses 24 months of training, then a 1-month embargo, then 6 months of testing, and advances by 6 months each time across 61 months of history. In each test block, the first 2 months are used only to warm up a trailing feature, so they are not tradable. How many tradable out-of-sample months do you score in total?