Obviously the "safe" option would be to follow recommendations and just do it - 5 years or 70,000 miles doesn't mean 5 years or longer if you've not done the 70,000 miles - belts degrade with age as well as mileage.
However it's worth considering what sort of running you've been doing in clocking up those 34,000 miles. Frequent short trips with a lot of stop starting are more stressful for the belt than longer journeys where you may be cruising at constant speeds - ie. motorway/main roads.
I don't have much experience with the 16 valve motors but the 8 valve engines don't seem to be particularly hard on belt life and it's rare to see someone posting about a belt failure unless they've clocked up "stupid" mileage or suffered something like a water pump bearing failure.
We've had Pandas in the family for as long as I can remember (and I'm 77 years old now) and we also now have a Punto 1.4 8 valve. None of the cars do particularly high mileages but I stick to the 5 year interval and always do a water pump too (you can buy an inclusive kit at very reasonable cost, certainly under £100. If you're getting a garage to do it I'd strongly recommend an independent Fiat/Italian car specialist where you can probably expect to pay around £450 but it can vary quite a bit depending on where you are and what local labour is charged at. I recommend a specialist because, although the belt is not a difficult one to do if you know that engine, it's not too difficult to get it one tooth out if you're not familiar with them - there are lots of posts on here from people who have had a go themselves and ended up with this problem. It's also sometimes necessary to do an ECU reset (called a Phonic Wheel Relearn) which can only be done with an appropriate scanner (like
Multiecuscan) or the dealer computer and it's unlikely this tool will be available at a garage not specializing in Italian cars.
By the way, regarding this need for a Phonic Wheel relearn. If not done as part of the job you may find the car will be happy and it may not. It's all about the ECU's perception of the relationship between the signal sent from the cam sensor and that from the crankshaft sensor. When the new belt is fitted there may be a small change in this relationship which the ECU can't account for (after all, it doesn't know a new belt has been fitted, it just "sees" that the two signals are not quite relating as they previously did.) There doesn't seem to be a definitive "Phonic Wheel" fault code in the ECU's memory so what it does is post a code which relates to cam timing/ignition system so what you find is that, usually after the first time you've taken a run out in the country or used the engine at higher revs for a while, it brings on the engine management light and posts a code which indicates a misfire. What you'll find though is that there's no obvious misfire symptoms - lack of power and jerking etc - although the code is saying there is. This is very difficult to diagnose if you don't know that what's needed is a relearn and there are posts on here of people who have spent a small fortune renewing plugs, HT leads, coils, etc, etc and still not getting rid or the fault code for a misfire.
Obviously a main dealer should do a "gold plated" job but I've seen people on here saying they've been quoted really silly prices (I was when I enquired of my local main dealer) and often the main dealers don't automatically renew the water pump which I consider to be a "must do" as it's bearing is part of the belt drive train so, if it fails before it's time, you'll be stripping it all down again to fit a new pump.
Hope that all helps. The belts seem to be really very robust so I don't think you should be worrying unduly but, as a failed belt will pretty much write the engine off - valves and pistons getting overly familiar with each other, it's only the earlier 8 valve engines which were non interference - if it were me I'd be factoring in a belt change in the new year - and do the pump at the same time as most of the preliminary strip down is the same regardless of whether you do the pump or not. Anyway, antifreeze will be needing to be renewed at 5 years so there's another reason to do the pump at the same time and then refilling with new coolant. Oh, and just do the aux belt (fan belt) at the same time - you've got to take it off to get at the belt guards for the timing belt anyway.
As a final note. there are many of us on here who have licensed versions of
MES (
Multiecuscan) so if you're thinking of doing the belt yourself there may be a forum member near you who could perform a Phonic Wheel Relearn for you when you've done the belt - should it be needed. Always worth driving the car and watching for the EML, if it doesn't light up after a few days of use you probably don't need to do a relearn.
