If the General Pool Rollover Settings is disabled for the "Left to budget" and "Overbudgeted" amounts, but you have budget categories rolling over to the general pool, the budget category rollovers affect next period's inflow totals, but the rollover row is missing, so it's not clear what's affecting the numbers.

The rollover row should display as long as there are rollovers, even if the "Left to budget" / "Overbudgeted" rollovers are disabled for the General Pool.