Make a list of all your interests and check whether there are opportunities for you to do them in Broadstairs. Perhaps stay a few weeks out of season, attend a few meetings or get togethers to check that the people who do them are your kind of people.
My parents did diligent homework on the place they were thinking of moving too, stayed there a few days, visited their church, library etc and had a long and very happy retirement in the town of their choice.
Another friend moved to another part of the country on retirement based on happy memories of previous life there, but saw no need to do anything else. The town had changed beyond measure. She hated it there but could not afford to move and I believe her unhappiness contributed to her early death.