Items purchased after “Goods to follow” was stamped

I have a question to those who have moved to Canada from USA:
If you purchased some new items (after you stamped the B4 forms), i.e. those items were not originally present in those forms but you’re bringing them over anyway because they may be electronics etc, did you have to declare them when you were actually moving (i.e. while clearing your goods from customs warehouse)? If so, did you get taxed ?

Do you ever got an answer for this question? I’m currently in similar situation, looking for the same answer