According to the sales person,
rm 10 is the stamp duty, which is a standard similiar like what you apply Internet line from ISP, i guess is compulsory,
as for the 60sen, huhu, everybody know la huh siapa punya masterpiece,

as for the day you start use till your cycle date, an example, your cycle date which your data will be refresh, and is also your bill date is 4th of May,

24th april - 4th of May got = 11days.
the day you start use till your cycle date =
rm38 / 30days  then * 11days of usage  =  rm 13.93333 -> masuk rm 14 la ok, easy count.

then apply GST , rm 14 + 6% = RM14.84

Then , for the month of May to June = rm 38 + 6% GST (Again, masterpiece from... u know) = rm40.30

so the 1st bill you are suppose to receive by June 4th, will be like

Rm10.60 + rm 14.84 + rm 40.30 = RM65.74
THIS IS WHAT MY SALESPERSON TOLD ME.

End of report~~~~ thanks for reading.