The working life of ACN differs from projects.
Some start work at 630am and finish at 430pm.
Some start work at 830am and finish at 530pm.
Some start work at 10am and finish at ... 10pm-12am.
The project teams normally follow client's schedule, but most of them work beyond the usual 8-hour jobs.
They have their peak period where the team members will work throughout weekends for months until projects go-live; And off peak period that you can go home relatively on-time (relative, because it's still at least 1 hour later than your official work time).
There is ample opportunity for growth in ACN even for fresh grads.
They can undertake different/bigger roles in their teams to help drive meetings/sessions/discussion with stakeholders/counterparts. It depends on your ability to handle.
The only downside is the "work-life balance".
Despite the work hours, the learning curve for fresh grads who do not care about whether to pursue their own fields (esp for engineering grads who are deployed to their TACG groups) is actually rewarding.
If you prefers to pursue the field that you study (esp engineering), my advice is to go back to your field and look for a job instead.

AL depends on your job level.

For starters, it's 15 days.

Last I recall they hire all year round, based on project's requirement.
Don't hesitate to try anytime.