I live in Dover. The village of Aylesham is about 9 miles away. The following is taken from wikipedia.

By British standards, Aylesham is a relatively new village. It was established in 1926 to house miners working in the Kent coal mines. The heads of the first families to be housed there all worked at the nearby newly sunk Snowdown Colliery. It was planned to also accommodate future workers at two other proposed new pits at Adisham and Wingham, but neither colliery was ever built.

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Miners from all parts of the UK (notably South Wales, Scotland and the Northeast) seeking better wages and safer conditions, travelled to the South East to work at Snowdown Colliery.[3] Due to this the people of Aylesham have developed a unique dialect, which was the subject of a 2016 article in the Transactions of the Yorkshire Dialect Society. Most residents use the short [a] in words such as bath, as is common in the northern half of the country, and a schwa in words such as strut, as in common in Wales. Some older residents also use glottal stops for the definite article, as in Yorkshire and Lancashire.

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As the village expands the local accent/dialect will become more diluted. Words like jitty might survive, others like snap might well not.