Check if time is between two time inputs.

FYI: since you are already using TimeLib.h, here is how to get a unix time stamp from an arbitrary date:

#include "TimeLib.h"   

tmElements_t te;  //Time elements structure
time_t unixTime; // a time stamp

void setup() {
  Serial.begin(9600);
// convert an arbitrary date and time into a unix timestamp (since 1970)
    te.Second = 0;
    te.Hour = 0;
    te.Minute = 0;
    te.Day = 1;    //start date: Jan 1, 2000
    te.Month = 1;
    te.Year = 2000-1970; //Y2K, in seconds should be 946684800UL
    unixTime =  makeTime(te);
    Serial.print("unixTime = ");
    Serial.println(unixTime);
    Serial.print("now() = ");
    Serial.println((unsigned long) now());   
}

void loop() {}