Steve Bell seems to be confusing an Australian accent with a New Zealand one.
Here, in yesterday’s Guardian cartoon, the Australian Rupert Murdoch is ordering his tame policeman to arrest the Queen. His accent is caricatured by jocular respelling.
While both Australians and New Zealanders — but particularly the latter — can give the rest of us the impression that they are pronouncing DRESS words with the KIT vowel (Rebekah → Ribikah) and TRAP words with the DRESS vowel (shag → sheg), it is only New Zealanders whose KIT vowel is so centralized as to lead us to perceive it as the STRUT vowel. Australians, on the other hand, make it closer and fronter than in many other accents, nearer to [i].
That is the easy way to tell Aussies and Kiwis apart. Get them to say fish and chips. The ones who seem to say “fush and chups” are the Kiwis.
But in Steve Bell’s cartoon Murdoch is represented as pronouncing the Windsor bitch as “the Wundsor Buttch”. Since Murdoch is an Aussie, it would have been better shown as “the Weendsor Beetch” (though of course that too is an exaggeration).
The last respelling, throne as “thrine”, is an interesting attempt to reflect the characteristic Australian GOAT vowel variant in the region of [æ̈ʏ]. (This is the variant that Paul Kerswill observed in Milton Keynes a few years ago, leading to a flurry of media claims about the supposed influence of Australian soaps on British popular accents.)