There is still free storage: but it’s part of a time-limited trial. No more forever-free space.
If you add around 12GB per day: then that’s around 360GB per month? If we say that averages to an increase of 180GBm… at $0.004/GBm… then I think your Storj bill would increase about $0.72USD every month? (or less if you’re also deleting stuff)
Unless I did the math wrong?
I’d expect them to bill you against your credits every month, even if it’s less than a dollar.