Perhaps a slightly esoteric one…in the ”發票存摺 + 統一發票對獎機“ iphone app (used for storing and scanning receipts) there is an option to add your bank account details so any winning invoices are automatically credited.
However, during the adding bank account process (under 匯款帳戶) it asks for your ARC number, but the new the format is rejected. The old format works.
A workaround is to go to the Government einvoice website on a web browser and you can enter the details manually there: