Good point... I hadn't even looked at the description... I have received the C3 Premium Plaque Defence. I think the text in the description is a copy/paste error. There are always mistakes in this shop...
The brush heads belong in the normal household waste.
You can take the electric toothbrush itself to any shop that sells such devices for proper disposal, regardless of where you bought it.
The toothbrush can distinguish between brush heads and counts their use. For a brush, the rule is that it can be used 180 times, then the message comes. If you brush your teeth twice a day, that's 90 days, or 3 months.
And I believe that using the toothbrushing programme twice in a row (i.e. brushing your teeth for 4 minutes) counts as twice.
The statement that Galaxus has created artificial scarcity is not correct. If you were to check the prices at other retailers, including Philips itself, you would notice that the black version is effectively more expensive!
This is for a simple reason: the white version is used more often and therefore produced more. Larger quantity = lower cost price. Therefore, the white variant can also be traded at a lower price. Whether it matters whether you need black or white is a moot point. But for sure some people were happy about this offer!