Thanks for reaching out to us. If you have a sufficient balance available from Upwork earnings, we will use that to pay for your membership. If your balance isn't sufficient, we'll charge your chosen billing method. Kindly, follow up on this help article to learn more about Membership Billing for Agencies. As for your second question, when a bank converts a transaction, they will mark up the interbank rate to buy or sell a currency. Online calculators will not take into consideration the mark up that is applied. Since rates constantly change throughout any given day, the rate you received is the rate offered by our bank at the time your specific transaction was processed. I hope this helps.