If you are very careful you can use elapsedMillis.h but most people will find SimpleTimer much easier to use.
You still have a 3000ms halt (delay) to lose. Blynk has a 10s heartbeat that has been as short as 5s, Miss the hearbeat and you are disconnected from the server. Irrespective of the heartbeat sitting around doing nothing for 3000ms is bad form.
In V10 add a Serial.print or lcd.print for Setpoint1 to be sure it is working ok.