Analyst to Associate - How likely?

Hi Guys,

I'm an incoming intern in a coverage group at a mid tier BB (BofA/Citi/CS/Barcap). Although I haven't even done my internship yet, I am pretty confident I want to be an associate before moving into industry (no interest in PE/HF) so that I can get a higher position than as an analyst.

If I am even an average analyst, how likely is it that I can make the jump to associate without going to B-school? Will I have to lateral to another bank in order to hit associate? Will my bank force me out if I am not a top performer?

Also at the mid tier BBs, is it a 2 or 3 year analyst program? Have heard differing sides so I want to be clear.

Another question would be do the exit opportunities from analyst to associate differ significantly in industry (corp dev/startup)? Like would staying the extra year or two as an associate give me far better exits than as an analyst or is it similar.

Any advice helps! Thank you!