I have a doubt...

i.e. Level 4:

Earning Rate - 0.00002 BTC/min
Max Capacity - 0.009 BTC
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Max Monthly Income: "0.864 BTC"

Upgrade (costs): 0.25 BTC

Reach Max Capacity: 0.009 / 0.00002 = 450 min => 7.5 hours

    In 22.5 Hours - 0.027 BTC (three harvest in time)
+  In 1.5 Hours - 0.00188 (small harvest)

In a day (earning): 0.027 / 22.5 * 24 = 0.0288 BTC

In a month: 0.0288 BTC * 30 days = "0.864 BTC" ----RIGHT!
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Now:

Lifetime - 17 days 08:40:00

Earning: 0.0288 BTC * 17(º) days = 0.4896 BTC
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