Incorrect display of a stack size

Just started a new learning session (web app) with cards count (at the bottom of the page) equal to 0. Progress page showed 120+ cards in the repeat stack. After competing 100 cards (some of which I failed and had to relearn) I got 0 card in the stack (on progress page). Though Lingvist keeps throwing in "repeat" cards (that is expected, according to the initial estimation, but is strange considering current values). Looks like the math is pretty off here even for a perfect session,

I think this is because the previous day you didn't do all your cards at exactly the same moment, so they show up in your repeat stack on a rolling basis, not all at once at the start of a day.

You may call me rude or whatever, but for me personally it doesn't even begin to explain how it's possible to review over 120 cards in 100 repeats (the situation I've tried to describe above).

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