Signed up for the Far Eastern Department store app (don’t ask why - my girlfriend suggested doing that because of some coupon reason). New ID format not accepted, so I tried the old one which worked. During the verification at the counter (why do they require verification for an app?!?) the clerk was a bit surprised that the ARC number did not match. Then we pointed to the back of the card and he happily did the verification using the old number.
Ah, and when I went to the Taipei medial University on Thursday, their system couldn’t process my NHI card (which already has the new number). Apparently “something is wrong with the number” (of course it’s not their system, but the card!). They gave me a paper slip with a “registration number” which I should show on the next visit (but they didn’t give me back when I handed it to one of the doctors)