All these "top end" watches have the same problem. About three years after I bought my wife a very nice Omega the battery needed changing. I was told by the main dealer that this did not simply mean being changed, but Omega would wish to replace the hands as well!! Why? I foolishly allowed the watch to be sent away and it came back 8 weeks later with a bill for £200+. The jeweller told me that it was lucky it was an Omega and not another brand (I can't remember which one) as the time for servicing was 52 weeks!
Interestingly, when I took my old (25+ years) Omega Seamaster to my local jeweller for a new battery it cost £5. Either the manufacturer's approach to these things has changed with newer models or the local jeweller is more straight than the main dealer.