Last date is for issuing the TDS Certificate, which is 30th of the month following the Quarter end. There is no last date for downloading the certificate.
You also have to download form 16A before 30th July...(relating Quareter} Otherwise Penalty Of Rupees 100 Per day may be... Correct me If i am Not right ?
For issuing the certificate on or before 30th July you have to download it on or before 30th july only. The penalty of Rs 100 per day is for non issuance of certificate.