You could also try using Pdefn. Try updating it below while the Ndef is playing.
Pdefn(\pilot_variable, Pseq([1,2,3,4], inf)); Ndef(\stream)[0] = Pbind(\note, Pdefn(\pilot_variable)).play;
~pilot_variable = Pseq([..., ..., ...], inf); Ndef(\stream)[0] = Pbind(\note, ~pilot_variable).play;
Best Regards, Mads Kjeldgaard