I’m informed the British do read the time 6:30 as “half six”, a shortened form of “half past six”. So “inch an a half” might become “incuax”, pronounced as “in-cha” and containing the unnecessary U, and an X for that Norman/French faux lineage.

Naturally, Americans would instead pronounce it as “in-coh”, which would destroy any understanding when also speaking about Incoterms.