I'm not entirely sure whether I can early exercise. There's nothing about it in my contract though, so unless this is a default of some sort, I assume it's not possible for me. I can ask my employer though.
[1] https://serbinski.com/stock-option-compensation-us-and-canad...
It's worth checking with your employer if early exercise is possible, but it's not the default and it should be mentioned in the options documentation.
With NSQOs, in a way, there's less pressure to exercise earlier, because there's no holding period for preferential treatment (isos get better tax treatment if held for at least 2 years after the grant and at least 1 year after exercise); so with ISOs, you might exercise and then want to hold and have risk there... With NQSO, if the stock is liquid, there's no reason to not sell when you exercise. If the stock isn't liquid, maybe you want to exercise and limit your ordinary income gains and hope for long term capital gains. Maybe you don't... it's always a bit tricky.