Credits and product price would be formatted in the same way, with a currency symbol (e.g. 拢15).
Credits balance is shown as "10 GBP" and other amounts show as "拢10".

Discovered debugging an unrelated issue during support rotation.
Moved to Checkout Redesign for triaging.
This is fixed in the new Checkout flow. Closing.

Most helpful comment
This is fixed in the new Checkout flow. Closing.