Advice on first snowboard length?

I’m a newbie, it’s currently my first season, and so iv been learning to snowboard on a 140 cm and at times a 145 cm when a 140 isn’t available.

Ideally according to my weight and height, I should/could be riding a 145-150 cm.

If I decide to buy a board, what length do you guys recommend? I don’t leave near any mountains so I would only be riding once a year if I’m lucky :( which means I’m unfortunately going to be staying at a beginner level for the foreseeable future.