1) move the stalk to the first detent and release after: less than a quarter of a second, and you get the automatic three blinks.
2) move the stalk to the first detent and release after: more than a quarter of a second, and you will find that you get however many flashes that occur while you have the stalk moved - whether that is one flash, two flashes, or seventeen flashes.
I'll point out that you don't hav eto move it fully in to the detent position for the 3-blinks. Just pressure on the stalk to move it slightly then release it to spring back to "nuetral", and you'll get them...