If I earn a CAB overseas and I finish my contract, then reclassify to an 11B and get deployed again, can I earn a CIB?

Yes, but you can only wear one. Both are GROUP-1 awards, and only badge from GROUP-1 can be worn at the same time...
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Having a CAB and re-classing does not qualify you for a CIB. You would have to re-earn your CIB as a grunt.

Why don't you go to a VA hospital and talk with the disabled Vets about their badges and ribbons.. and how you desire to proudly wear one someday.. Make sure the deaf ones can hear you, so shout. I remember when a Young widow was presented a CIB, Purple Heart and Flag... she burried her face in the flag...Her husband in dress blues wearing his CIB, laid nearby. So what war are you hot to get into?

Yes, but you can only wear one of the at a time.