Jerome in 1821

As far as we know this is the first time Jerome is mentioned in England.
We think it is a trouvaille.
We now know he returned from a trip to the continent in 1821.As least that was he tells in this ad.
We can assume he was there also in 1820.
From then on we find ads saying he is back from Paris or the continent.
Why did he go back every year in July to the continent .....had this something to do to with his passport ..which had to be renewed every year????
Why did he stay a Dutchman all his life ? Why say he was a native from France.?
Why did not he apply for an English nationality?
It would be easier .
A lot of questions to start the New Year.
Which makes it A Happy New Year !!!!!