Abnormal upwork fees

[hanahakim]

Hello
I recently submitted a proposal to a fixed-price job with a 1000$ budget. On the application form, it says that upwork fees are 150$ and I get 850$. 150$ is 15% of the total budget, whereas all articles on this platform say that for over 500$, upwork only charges 10%. Any explanation? 

[wlyonsatl]

Per customer freelancers pay Upwork 20% for the first $500 paid by the client to the freelancer, 10% for $50- $10,000 and 5% above $10,000.

For a $1,000 budget that would work out to ($500 x 20%) + ($500 x 10%) = $150.