EWL,
The flight you mention was moved into a new day and had to be allocated an new "off schedule" flight number as no airline system can handle 2 flights of the same number operating on the same day.
Standard operating procedure for all airlines.
I don't disagree with you on this particular flight. But the practise of rebadging flight numbers due to a delay occurs morning, noon and night, and as I said in my previous post, it is just another deceptive means to fudge the real OTP figures, which of course DOTARS has been too stupid to wake up to.
Then again, another LCC that doesn't use the ACARS system often makes up their own call as to what time they are 'off blocks' and 'off the ground', it's amazing how fudging these figures also can create an impression of better OTP than is actually occurring !
Then again, you can fudge the figures if you are a Legacy Carrier by attaching the Pushback Tug to the aircraft ensuring the tug is parked correctly with brakes applied, then have the PIC release the aircraft's brakes while the Pushback Tug holds the plane still. As soon as the aircrafts brakes are released the 'clock starts ticking' and you can keep the piece of tin on the bay for another 4 hours if you want too !! Mind you, OPS starting smelling a rat and start phoning as soon soon as they see through ACARS that brakes are released but yet 30 minutes later the beast is not yet airborn !!!
Anyway, such is life !