As
@Artur5 told 3 months ago, the ARC's only reset when empty.
I removed all 4 carts when one was without ink (=no printing) and topped them up.
Since I had some feed problems with the cyan, in particular when nearly empty, I flushed the cart and switched to a fresh bottle of (octopus-office.de) ink.
It is better now.
As long as the carts are full enough, the Maxify is a charm.
There is a difficult to understand pressure mechanism, and the OEM carts handle this best since they have a bag inside.
But no outlet valve, so refilling before empty is a real mess, the ink flows in the printer (Canon did a good job to scare off potential refillers

).
It takes also a long time plus one or two extra cleaning instructions (and I suspect a lot of ink in the - not exchangeable - waste container) to prime the printhead again.
I was reluctant to run the printer with chips showing empty, but you don't need to do any action to switch off ink monitoring and I have no indication the printer does more purges or takes other revenges.
So I play with the idea to install the refillable carts again and refill them via the plug in the back without removing them from the printer.