Defining covariates and blocking factor for repeated measures

Hi all,

I am trying to analyze one data made of two groups where I have three time points. I am running the Linear Models with covariate adjustments, but I am unsure how to define the covariates and blocking factor.
I was able to get some help by looking at this post: Best format/analysis for repeated measures?

The advice was to set time as “Covariates (control for)” and subject as “Blocking factor”; however, the data was loaded as “Multiple factors/covariates”. What if I load the data as “time-series + one factor”? Is the subject already accounted for or should I add it in the blocking factor as well?

At the top of the page, there is some text recommending to keep the blocking as “unspecified”. If I follow this advice and add subject as a “Covariates (control for)”, then the results are quite different. I tried accessing the book linked in this page but I don’t have access. What is the rationale in this case?