Hi @auromira Welcome to MadeForTrade community.
Iceberg order will auto-slice the orders beyond freeze limits… for such use-cases where one has to place larger orders than freeze limits - we suggest using iceberg directly over basket orders.
Your orders will get rejected only if there are margin limitations, ensure you have adequate funds or margins available when placing large orders.
We have a detailed post on Order Execution capabilities of our transaction platform DEXT: Dhan: Understanding Order Execution Performance, Speeds and Response Times on DEXT
We wouldn’t comment specifically on time take for 99 orders to execute on exchange only because we have seen even some seasoned traders at times do not understand that execution of any trade, single or multiple depends on exchanges. That said, Dhan has many large traders and Iceberg orders are very very common for us. We have seen traders holding positions in excess of > 50,000 lots via Iceberg and exit them on a single click.