Swift started to use grp for the front around MY 2012. They are more robust than ABS but more difficult to keep a shine on as the gel coat was quite thin.
As said above ABS are thinner (lighter) but do have a tendency to crack either due to poor manufacture/ assembly or because of flexure. I’ve had three ABS panels replaced on two caravans under warranty because of cracks. On another thread re Lunar the OP had a cracked panel on a new Lunar. So most makes seem to be affected. Such is progress in the caravan industry, but eh we get microwaves, heating apps, self levelling etc whilst the fundamentals are poor. A new panel would set someone back over £2000 plus any damp repairs caused by its failure.