Hi Marcus, Rosie!
Marcus, the side lever gear for the first of these patterns was ordered between 28 June 36 and 8 July 36. (!) I'm not sure how long it would take for the finished product to arrive in the shops after that date.
Dome footed vases, 8" and 4", a non-footed salad
like the one in the back here, and non-footed 'nappies' (Crown's term for what Americans call a 'berry bowl' and Aussies called a 'sweets bowl'), were all ordered on 28 June 36. The
'footed sundae' with a catalogue number of 1251, and a rose bowl 1228/9 were ordered on 8 July. Some of the forms had been torn from the records, so there may have been more as well.
Might this suggest an earlier date for the Hermanshütte production?
Crown used to pay someone to travel around Europe picking up interesting patterns for copying (information again from Tariff Hearing files). This is why Crown's Grimwade Crystal tends to look like Inwald or Webb made years earlier.
Rosie, do you have a record of which pieces you bought from Australia? In general, the Australian ones appear mostly in clear, green and amber - I've never seen any in the Australian blues, emerald green, citron or any of the other obviously Australian colours, but it wouldn't surprise me if something turned up one day. There are plenty of the Hermanshütte pattern here as well, so some of them might have been going home, to the Northern Hemisphere, anyway.

Love your collection, by the way!