Most certainly yes! See, the opening rank is the rank of the person who had the highest rank in that branch or the person who was the first one to get the admit an the basis of rank, now if you have a rank higher than that person, then you will be the branch opener!

However, the rank you told might be of the last year, and in CSAB, the change of ranks may be drastic on an year-over-year basis, so look out for that.

Hope I have answered your question. All the best!