Hi @dilip.td,
I would recommend continuing to categorize both transactions as income. You can then budget $250 towards an expense-type category of your choosing e.g. General Savings. This works conceptually because savings are, simply put, budgeted expenses that have no actual transactions yet (Budget - Actual = Savings). 
If you are using the Savings Budget sheet, which I highly recommend, you can allow unspent (or overspent) budgeted categories to accumulate from month to month.