simplifying double affricates

The island of Montserrat, where I have spent the last three weeks (pictures), has the usual anglophone Caribbean spectrum of varieties ranging from a creole (which can be pretty impenetrable to those not familiar with it) up to the local variety of Standard English.

The syntax of Caribbean English Creole includes a vivid method of topicalization by fronting and repeating. You can do this not only with noun phrases but also with verb phrases:

a kɪl i mi a kɪl i (is kill him I PROG kill him) ‘I’m going to KILL him!’

Less dramatically, here’s a neighbour telling us about ongoing building works further down our road:

a ˈkaŋkriːt dem a ˈkjaːs doŋ ˈdeə

which means ‘they’re casting concrete down there’ and like the first example demonstrates two distinct uses of a, first as the topicalizer particle at the beginning (‘it’s concrete that they're casting’) and then as the progressive particle with the verb (a kja:s = (are) casting). Notice the combination of Standard English technical language (casting concrete) with Caribbean grammar and phonetics.

In the local pronunciation of Standard English one striking feature is the reduction of affricate sequences. In most varieties of English an affricate is preserved as such when followed by another affricate: we say each chair with -tʃtʃ- and orange juice with -dʒdʒ-. But in Montserrat tʃ and dʒ are reduced to unexploded t and d respectively when followed by another affricate. Not only do we get -ttʃ- in each chair and -ddʒ- in orange juice, we also get -ttr- in each trip and -ddr- in a large drop.
For months I was trying to puzzle out a radio jingle played on the local radio station, Radio ZJB, to advertise the Bank of Montserrat,

But for iːt transaction
You will get swift action…

— until suddenly I realized that what they were singing was for each transaction.