From a legal point of view, you can't fly a G-registered aircraft commercially without either a UK or a JAR license.
If I understand you correctly (not quite sure I do, so correct me if I'm wrong) but the training you are looking at getting would not give you that? Therefore, you would have to convert your license to JAR before applying for jobs in the UK.
The more hours you have, the less arduous the conversion is, but the general opinion seems to be that it's easier to get the JAR license from the start. This isn't an area that I know much about, but there are plenty of people on these forums who have been there and done it.
Apologies if I've misunderstood you.
FFF
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