When to decide?

C

At present i have 3 PhD interviews coming up, and i have applied for a couple more projects which i would at least expect an interview for.

My problem is i am unaware of firstly - how long after the interview the decision process takes ( i appreciate it will vary from department to department)

Secondly i dont want to turn any projects down as i like them all, however i do have some preferences, how long until you have to decide?

As afore mentioned i am aware these time frames probably vary but is there a rough estimate, i am sure other people are in / have been in this situation.

Thanks Chris

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