Hmm.. In a slightly varied situation...

Resigned to join Company A...
- Company A supposedly needs to wait 1 mth after signed offer letter, but I extend to 2 mths bcoz of avoid losing bonus pay out in current company.
- Company A requests earlier join date. So requested early release (self compensated current company) and join Company A earlier.
- Company A pays in total package the expected amount I asked for.

Started in Company A a few days, and got offered from Company B.
- Company B pays about 10-12% more than I asked. Amount asked is same with both companies. But Company B comes with much more benefits overall.
- Company B is the one I always wanted to join since graduated.

So, would like to enquire if:
- Is it bad to terminate employment with Company A after working for just about a week?
- Supervisor has planned out training plans. Currently still in learning period only.
- Notice period is one week during probation, but is it possible to be released since there's no point for me to sit in the office for 1 week where I only do learning at the moment? It doesn't seem practical if I continue to do study and then leave one week later. No tasks assigned yet so nothing to handover or transition.
- Will I get blacklisted by Company A?
- I guess it will not leave a good impression to Company A and cause a lot of inconvenience but Company B's package is way more attractive. And I don't think Company A can match up to Company B's package.

Opinions from you all?

Thanks in advance!