I'm a bit clumsy, and managed to overfill it so that the dipstick is about an inch over the high mark.

Is this an issue? Any suggestions?

I'm going on a 600km trip on Thursday, and the same distance home again a week later.

Will it be ok, or should I get it drained before then? Is that a complex operation?

I'm not a DIY guy, so I'd have to take it into a shop. Any ideas how long it might take?

Here's hoping all is well :)

Thanks in advance!

Yea thats bad.

Undo the sump nut and let some out. If you run too much oil, the crank can turn it to froth and you end up with a dead engine from oil starvation

I can't do any car fix stuff myself, only computers :)

Will it be ok for a while, or should I get a shop to do it before my trip on Thursday?

As someone who overfills the sump by 1 cm on the dipstick every time he does an oil change, I can suggest this:

Start the car, open the bonnet, listen to the engine. If it sounds normal, it is fine. If it makes "GLOOOOP GLOOOOP" noises, it is not.

Daughter, in her younger days, added an extra 4 L of oil to the engine (Toyota). She was doing an oil change, but forgot to drain it first. lol No harm done once drained and refilled.

(Yes, in theory the crank can hit the oil and stir it up and cause all sorts of problems, including popping oil seals out of their seats, wrecking the engine, etc. Does anyone know the distance between the top of the normal oil level and the bottom most swing of a crank weight?)

I Put too much oil in a Toyota Corona a few years ago. I figured it out because of the pools of white smoke behind. Drained the extra oil out and no problems with the car.

As someone who has overfilled oil in an engine (unknowingly) and continued to drive it, get it tended to ASAP if you're planning on going on a extended trip, or any trip really.

Not long after I got my license, I had a shitty N13 Pulsar which, at one point, had an oil light show on the dash while I was driving. As naive as I was then, I thought it meant the oil was low (as opposed to, say, a sensor problem), so I stopped at a servo and filled it with a litre of oil. Back out onto the highway and the engine shits out a whole heap of smoke, enough to blanket both side of the M1 and upon inspection on the roadside, surely enough I overfilled it. So I drained the excess on the side of the highway, which was a litre and a bit (yes, into a container), continued driving but it died about a hour later. From the sounds it was making, it was pretty terminal (I think possibly bearing related). I was somewhat lucky in the sense that the car was a bucket of crap and only cost me a thousand bucks. It was a learning curve for me to say the least.

So yes, overfilling it can very well leave you stranded.

the engine shits out a whole heap of smoke, enough to blanket both side of the M1

almost sounds like tommo's golf.