Thanks everyone.
The powder pockets are inside the pasta tubes: and no amount of stirring will shift them.
I have reached the conclusion that if you enjoy Huel H&S Pasta al dente, then powder pockets come with the territory.
Also true of just following the instructions.
That said - I would like to see Huel adjust the preparation guidelines to reflect the reality experienced by users:
…For the sake of both simply honesty and improved customer experience.