reflux is just projectile vomiting of most or all of a feed. Stanley would do it about 15-20 mins after finishing a bottle, but only once or twice a day.
I believe the best way of treating it is to give the baby thicker milk. Some formulas are thicker (like Stanley's Comfort or SMA Staydown which you can get on prescription) or you can add Gaviscon powder to thicken it up (available on prescription).
I think it's pretty common, particularly in prem babies where the stomach valves might not be fully developed yet. There's quite a few babies on here who have it, Sami is your expert though!