I'm getting different results for the Box-Cox parameter using two different methods. Why is this happening? (I'm trying to follow the Mathematical Adjustments subsection in FPP3.)

I get 0.03146112 for guerrero(h02$Cost, .period = 12), where .period is the length of the seasonal period.

The documentation for the guerrero() function also notes that the forecast::BoxCox.lambda() function will give a slightly different value if the data does not start at the start of the seasonal period, and the h02 data starts in July. After converting H02 from tsibble to ts format, the value from forecast::BoxCox.lambda() is 0.03147061.