The payment gateway BitPay calculates how many bitcoins equal a USD price and then give that amount (minus their fee) in USD to Namecheap within 2 days.
"It does not matter how many bitcoins we collect, how long it takes to collect them, what we can sell them for, or how long it takes to sell them."
"It does not matter how many bitcoins we collect, how long it takes to collect them, what we can sell them for, or how long it takes to sell them."
https://bitpay.com/bitcoin-payment-gateway-api