Upvote:0
There is no legal limit on how much time you can spend in the United States in B-2 status within any 12 month period. Admission will generally be limited to 6 months at a time but it is not impossible to be admitted for another 6 month period shortly after a previous visit has ended.
Given your circumstances it seems likely that you would be admitted for another 6 month period since you have several positive factors including ties to Canada, compliance with the conditions of all previous visits, and the fact that your parents apparently had enough money to send you to college in the US so you have little incentive to seek unauthorized employment on this trip.
Of course, it is impossible to predict for certain whether you will be admitted but I would suggest relaxing a bit because the consequences of being denied admission at a preclearance location, as a Canadian citizen, are very light. The worst thing that is likely to happen if you are denied entry is: (1) the CBP officer puts a note on your file that will cause you to be scrutinized more closely on future visits to the US, (2) your NEXUS membership gets revoked.
Upvote:1
Your understanding is correct. You can be admitted for up to 6 months and there is no rule preventing that. Or the officer can, in his/her discretion, admit you for shorter than 6 months or deny you entry altogether.