HDS asked the escrow agent to return the $20,000 and asserted that nothing was owed to CP even though HDS continued to use the programs"If CP in fact had half-completed the job on June 6, would it then have been entitled to $10,000?
No, because "within one month of completion" would, in these circumstances, be interpreted to mean "within one month after completion."
Yes, because June 6 was within one month of completion. 
Yes, because CP had done one-half the job. 
No, because of a constructive condition precedent requiring at least substantial completion of the work before HDS would have a duty to pay 