I am unsure as to why Voting and Rewards have to be redeemed exactly 24 hours since the last time you have done it.
This is an inconvenience to honestly quite a few people, especially those who need to go and work as all different hours of the days, as you may vote at 1pm on say Monday, however Tuesday you are working a shift until 6pm which means you can't get online and vote until you get home around say 6:30pm, this could mean Wednesday you're doing an evening shift working until 10pm, this then means you can't vote until 10:30pm and so forth, constantly adding up hours or forcefully having to skip a day in order to reset it back to an earlier time.
Unsure as to why it can't be done when the vote-sites reset, they all pretty much reset on a 12 hour-ish basis meaning they reset around 00:00 (depending on timezones of course). This then could make it easier as anyone can vote at any time of the day and get their rewards, while then coming on the next day and voting again as a completely different time, still receiving rewards.
Issue someone has said: "But then someone could get 'extra' rewards". Answer to this is no they couldn't, because if you voted on say Monday at 23:58, and then voted at 00:00 (this is then Tuesday) meaning 2 sets of rewards almost instantly however meaning that whole of Tuesday you cannot vote again until 00:00+ Tuesday night A.K.A (Wednesday). So the "extra" rewards is not possible to get.
Rewards is the same thing, you have to do it exactly 24 hours since the last time, which could be on a daily basis to reset at say 00:00 as well. This then also doesn't get users "extra" rewards as they would still need to wait till the next day to get a new reward.
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