In "The Red-Headed League" by Arthur Conan Doyle, where does Holmes think Mr.Wilson has been in the past year?

Early in the story Holmes makes the following observations about Jabez Wilson to Dr. Watson, who has been watching Wilson and trying to make his own deductions about the man:

Sherlock Holmes' quick eye took in my occupation, and he shook his head with a smile as he noticed my questioning glances. “Beyond the obvious facts that he has at some time done manual labour, that he takes snuff, that he is a Freemason, that he has...

Early in the story Holmes makes the following observations about Jabez Wilson to Dr. Watson, who has been watching Wilson and trying to make his own deductions about the man:

Sherlock Holmes' quick eye took in my occupation, and he shook his head with a smile as he noticed my questioning glances. “Beyond the obvious facts that he has at some time done manual labour, that he takes snuff, that he is a Freemason, that he has been in China, and that he has done a considerable amount of writing lately, I can deduce nothing else.”

Wilson confirms that he has been in China, but that was apparently when he was much younger. He obtained a Chinese tattoo on his wrist and still wears a Chinese coin on his watch chain as a souvenir. Holmes points out that Wilson must have been doing a lot of writing lately because of the condition of his coat-cuffs. The right one is shiny and the left one has a smooth patch where Wilson has been resting it on a desk.

Beyond that, Holmes does not venture to deduce where Wilson has been in the past year. That would seem to be beyond Holmes' powers. We learn from Wilson's account that he has been working at the office of the so-called Red-Headed League for the past eight weeks of this year. Before that he was spending almost all his time in his pawnshop. He has not been anywhere else in the past year or in quite a few years. He tells Holmes:

"I am a very stay-at-home man, and as my business came to me instead of my having to go to it, I was often weeks on end without putting my foot over the door-mat."  

The author, Sir Arthur Conan Doyle, wanted to establish that Wilson had been out of the country for many years, either in China or at sea working as a ship's carpenter. This would explain why he might not have heard of the formation of the Red-Headed League, which his assistant told him was big news in London when it happened.