Tiptronic Lifetime Oil ????

Apologies if this has been done to death , but I have a 2004 A4 3.0 B6 quattro , that has developed a tendency (when hot) to have a few issues with the Tiptronic box.

When cold the car behaves perfectly, it needs to be driven for an hour plus in normal traffic or sit in queuing traffic traffic for 10 minutes for this issue to appear. The issue is either a slow engagement of drive from a standstill (and then arrives with a bump) or a tendency to change up gears a little earlier than expected (not quite as smooth). When the problem 1st manifested I did get the "all gearbox dash lights in red issue" but this has never reoccurred

I took it to my local gearbox gurus, who drove it for an hour plus with the diagnostic computer plugged in ,but no faults showed up (even though the symptoms eventually did) , and even the original "all light in red" did not seem to be in the memory, so I am scratching my head a little.

The fact that it only happens when its hot suggests Oil to me , but I am told these gearboxes are usually quite tough and the oil is in them for life. The car has full service history and just covered 120K

So the question is , is there value in changing the oil for a couple of hundred quid or does this sound more like a wiring or ECU issue.

Any thoughts are welcome

Thanks Paul, That's pretty much where I am heading , but just wanted to check I wasn't missing anything silly.

Any suggestions on the best place to source the ATF (or does it have to come from VAG?)

Thanks Paul

Just been quoted a fixed price by my local Audi main agent (Southend Audi) of £ 175 including the parts, labour and VAT , which seems pretty far as the job does looks a little bit tricky,

Thanks to all for your comments

I did ask the young lady who quoted the £ 175 if the price included the filter (she said yes) , so I am assuming requires removing the pan? Does it seem a bit too cheap for removing the pan and filter etc?