In both cases GNP is increasing. In case 1 those who are saving now are saving from a greater income than the past income of those who are now spending from their savings. In case 2 those who are saving now outnumber those who are now spending from their savings. In both cases the instantaneously measured rate of saving exceeds the instantaneously measured rate of dis-saving for the economy as a whole. In both cases, growth is financially enabled through credit expansion.
Special problems arise in national accountancy if growth departs from steady-state.
Debt thereby accumulates exponentially compared to consumption. Increasing real income goes to fewer and fewer recipients. The solution requires that purchasing power be made available to industrial and final consumers that was never costed into production in the conventional manner. I is a nonsensical proposition.