@InvestBright For book building issue, price band is provided. While one can bid at any price within this range, retail bidders also have facility to quote at cutoff price. Cutoff price is price finalised at the end of bidding process at which shares are allotted and retail applicants choosing cutoff give their consent to accept at any price finalised. HNIs do not enjoy this privilege and hence should not tick or opt cutoff price. If they wish, they can bid at max price of price band, but have to add the single bid price manually.
For second part of your question, it is not a correct statement that sHNI applicant will always have better allotment chances than retail. It all depends on subscription levels in each segment.