I am not sure exactly what you're after with your question- a stop consonant is a sound made by stopping the flow of air, like /p/, so it doesn't necessarily mean consonants that are not pronounced as I understand it.
In the UK, the glottal stop (not pronouncing the /t/ in bottle, etc) is regional, so there's no clear national pattern- it's associated with London dialects, though its use is wider, but not universal. Dialects, which are still strong in British English, do things sufficiently differently to make it pretty difficult to make a national variant pattern. Other than this, we tend to change sounds to make them easier in connected speech so /t/ can become /d/, etc. It's also affected by factors like age- the glottal stop is becoming more widespread among younger speakers outside places like London.