Man, going from five doses down to four on the newer pens sold in Australia stings if the pricing didn't move with it. Essentially a quiet price hike on an identical box. That thicker black plunger design gives it away too, since people have used that exact trick to pull leftover medication out of the chamber for quite some time already. My pharmacist brought up earlier this year that the manufacturer was reworking the pen, though I'd assumed the dose count itself would stay untouched.
For anyone new here and curious what the so-called bonus dose actually is, it's just leftover liquid still sitting inside once you've clicked through every marked dose. Some folks are able to extract a genuinely useful extra amount using a syringe, but I'd recommend checking a couple of tutorials first so your actual starting dose doesn't get thrown off by accident.