Actually this seem to work
new task -s2/2/17at10am -d 2/2/17at2pm rmd 9am
new task -s2/3/17at3pm -d 2/3/17at5pm rmd10min
So it seems like space before -d seem to be the key element here. if there is space before both -s and -d then dates seem to get messed up. Either way guess the parsing need to be smoothed out.
Thanks Ray & Stéph