Hi according to some of the Autodata workshop books I have that cover all makes of car including SEAT.
This is what they state below :
SEAT Ibiza 1.4 8v 1995 to 2005
check and replace cam belt if necessary every 60,000 miles or every 5 years which ever comes first.
Book times for cam belt replacement:
1995 to 1998 (1 hour)
1999 to 2010 (2 hours max)
SEAT Ibiza 1.4 16v twin cam 1999 to 2010
These can have 2 cam belts fitted.
check and replace cam belt if necessary every 60,000 miles or every 5 years which ever comes first.
Book times for cam belt replacement:
1999 to 2010 (2-1/2 hours max)
NOTE!
Don't just replace the cam belt you'll more then likely need to replace the belt tensioner pulley and idler pulley, as these can become notchy or bearings will be worn, you'll know this once you check them for free play and how they feel / sound spinning them up.
Also it's worth checking to see how the water pump looks, any signs of wear or leakage replace it.
So in theory your
Ibiza should have had the cam belt changed at least twice in it's live by mileage 125,000 or 130,000 miles, if there's no clear evidence in the cars service history of replacement, then get it done ASAP.
Hope this helps
Si