Stories cannot be tested in time before the sprint ends

We have a great team delivering quality user stories. As per our practice, we test the stories as soon as they get developed. Recently we have added three more team members to our existing team of four as the management wants to plan a quick release of the MVP. The problem we face right now is that stories are delivered late for testing purposes - almost a day before the sprint is due for completion - and the testing team faces a lot of pressure to analyse and test the stories on time. Our testing activity is included as a task in the sprint, therefore if the stories are completed and their testing is not carried out, the sprint remains incomplete.

Posted By - Ivan