If you have already voted during the first voting period, you will not be able to vote again during the second voting period as your vote will have already been locked in. You are only eligible to receive additional packs for any matches your champion wins after you have chosen them. If you vote during the first voting period, you can earn up to 6 total packs (including your participation pack) depending on how well your champion performs. If you vote during the second voting period, you can earn up to 4 total packs (including your participation pack).