Hi TK,
That's a great question. The ballots are returned in a randomized (but stable) order on download, so it is not possible to correlate voters to their ballots based on times.
From a more technical standpoint, we don't store creation timestamps with the ballots, and our underlying persistence layer does not use sequential ids, so we wouldn't be able to order anonymous ballots by time cast if we wanted to.
Best,
-- Ana
Team OpaVote
https://opavote.com