You only get to deduct the accrued interest paid as you actually collect the interest. So if you paid $50 of accrued interest when you bought Bond 1, and $100 when you bought Bond 2, and you collected $130 on Bond 1 and nothing on Bond 2, you get to deduct the $50 paid (because 50<130) and carry the rest forward (because 100>0). Make a note for next year's file.

Same theory as the true up of real estate taxes at closing, when the payment period doesn't line up.