I have always had access to any stock or eft as they traded premarket or after market.
The issues as I discussed was futures such as ES. They can be seen on investing.com also, but really needed to see them in a full screen format. I usually check futures each night just as I go to sleep, not that I can do anything with them since I don't trade futures. But it does tell me what I might be able to expect in the am. However there were plenty of times a few years back where futures reversed when Europe opened.
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