Training cost estimate far lower than the confirmation quote

Hi all, I’m new to Roboflow and on the free plan (10 credits/month). I’ve hit this twice.

The summary page estimates about 2 credits and 90 minutes. After I click Start Training, the confirmation quotes about 10 credits and 4.5 hours. This time it said 9.73 credits when I only had 8 available, but training still started.

Also, I cancelled an earlier run and was charged 1.87 credits.

Is the confirmation number a worst-case reservation or the actual charge? Could the summary page show the same figure? I only have a screenshot of the confirmation screen, attached.

I’ll reply with the final credits used once this run finishes. Thanks!