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Don't grow older than 255 or else it will overflow
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A photo of a cake with 8 candles in a row. The first and fifth candle from the right are lit. The caption reads "Happy 17th Birthday"
I use that style of birthday candle, but I only place as many bits as needed.
The year before adding a bit then has all candles lit, the next has only one lit
Though the new bits don't come very often. My last was 31 to 32, my next will be 63 to 64, I don't like my chances to see one after that