Apply now or wait a year?

So, I'm in the UK and plan to move to Detroit Michigan in the summer of next year.

My plan is to try get in the Local 1102 Union for a Millwright Apprenticeship

I know the wait times to get through the list of applications can be months, so should I apply now (and can I do that whilst in the UK) to get on the list early, or wait til I'm already in the USA physically?

Any help would go a long way, thank you.