We have a nonperforming sub, whose contract was supplemented by another. They provided a preliminary notice, but have no right to their full contract due to change orders written for supplementing their work. We as the General are due change orders and retention on the contract with owner yet, so are questioning if we should be asking the owner to file the notice of completion on the job yet or not. This would shorten the lien window that the sub would have, but could possibly hurt us, as we have open items with the owner yet. What is advisable?