Sometimes it may be an advantage to downgrade the code of an <a href="https://de.wikipedia.org/wiki/Intercity_(Deutschland)" class="extiw" title="de:Intercity (Deutschland)">Intercity</a> to <a href="https://de.wikipedia.org/wiki/Regional-Express" class="extiw" title="de:Regional-Express">Regional-Express</a>,<br>allowing by such a <a href="https://de.wikipedia.org/wiki/codesharing" class="extiw" title="de:codesharing">codesharing</a> its use with cheaper tickets, instead of sending another train only for that purpose.
<a href="//commons.wikimedia.org/wiki/User:Sarang" class="mw-redirect" title="User:Sarang">Sarang</a>
<span class="int-own-work" lang="en">Own work</span>