I just played a normal game and solo queued. We won in just under 40 min and I only received 95 IP, it was also my first win of the day and I haven't queue dodged at all. Bug?
Next game you play it should pop up with a thingy saying you've recived a bonus from a previous game played, and that'll be your win bonus from that game.
One of your leaves may have been recent enough that your non-leave bonus is not the max of 23 bonus IP.
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