In response to your question about how long it'll take you to make shodan.
Standard question... there are a couple of good aikido FAQ areas to look at. For newbies, I suggest you find them and read as much as you can.
For this question... It depends. Of course what it depends on is: YOU(your intent, your "tools" you bring with you, how much you're willing to practice, how vunerable you are, your life situation, your future...); YOUR TEACHER/INSTRUCTOR (who they are, how good they are, who their teacher/s were, how you relate to them...); YOUR DOJO PARTNERS (who they are, how good they are, your relationship with them...);and as Tennessee Ernie Ford used to say, "if the Good Lord's willin and the creek don't rise."
If you want to know the best question about how long it'll take... ask your seniors what the average length of time to shodan is in your dojo and organization. There's are real answer to that question.