It’s the same for the Gen5 launched earlier this month. I suspect they don’t sell accessories right off the bat. Rather gauge the amount of interest they have before creating stock. 

I signed up to be notified for stock on this: Explorer case 972069-01 | Dyson. The edition I purchased came with the quarter-turn case. 

I took the plunge and ordered Prussian Blue/Copper version. Worth every penny of the extra £80. 

Ah, now it’s in stock . Totally worth the extra, bummed I couldn’t order this one. Still enjoying my non-Absolute+, @Stuart, please see if Dyson can add the copper mask as something that can be purchased separately. Eventually, people may need to replace them too!

yeah been waiting for the accessories to come in stock as well. that hard case is first dibbs!

i wish i could get the ¼ turn case because i prefer that over the one you want.

do you live in the US?

EDIT -- seems you are in the UK since the link you provided is from the UK. id give you that explorer case if you were here in the US. probably a lot more shipping cost than the value of the product id imagine.