Tamzin Outhwaite playing Kelly Anders is made to use two (at least) Americanisms:
Her future rank - lieutenant - should be pronounced "lef-tenant" in English whereas she says "loo-tenant" "Mercan" style.
She also refers to "ass" whereas in English the word is "arse"
Deobia Oparei playing Spanky has his language Americanised too.
Shame, it would also have been better to have more realistic actors.