I know that a vast majoriry of Sinn owners here will call this sack religious, but I feel it would work. Something about sending the UX back to germany to get the battery changed, and re-oiled sounds silly. I have never seen a picture of the screw/porthole used to fill the case, but if it is opened with something like an allen wrench or torx-bit, then what can be so complicated about filling up a watch case. It cant be any more difficult than pouring some oil into a 4-cycle weedeater (which I just did, and got the idea for this).
Here is how I would do it....
1. Unscrew caseback, oil will go everywhere so do it in a tupperware bin.
2. switch battery out
3 screw caseback on.
4. Warm oil up (about 110 degrees farenheit) to let it become nice and fluid/runny to prevent air pockets.
5. fill until it is overflowing.
6. Let it sit port-hole facing up to get back to room temperature (thus contracting a bit)
7. fill the last bit up, (it couldnt be more than a drop)
The only things I think that sinn might do differently is using something to pressurize the oil while filling (probably just pressurizing the enviroment the application is being done), another thing sinn probably does is that they make sure the membrane is "out" or just in the position that will allow the oil to contract.
Also, is it possible to order a UX without the oil?
Any pics of the oil-fill port around here, Ive never seen it.