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I have a circulation visa(valid till march 2020) issued by French Embassy valid from march 2017. In my application I mentioned I will be visiting France(from London) for 4 days in mid April (which I will be), but due to some Official training I have to visit Greece(from London) for first two weeks of April, come back to London and then travel to France(as per the dates mentioned in my visa application), can I do so ? In a nutshell can I enter Greece on a schengen visa issued by France, which was earlier not the plan? Does it impact my entry at Greece or France?