In 2015 the northbound platform at High Wycombe station was extended to allow longer trains to call. This entailed the closure of the subway and its replacement by this new bridge. It is interesting to see that 165019 on the terminating service from London has stopped at the south end of the bay platform (behind the fence). This makes it easy for passengers who want to cross the line on the new bridge but makes a longer walk for those who need to leave the station or are starting their journey here.
<a href="//commons.wikimedia.org/wiki/User:Geof_Sheppard" title="User:Geof Sheppard">Geof Sheppard</a>
CC BY-SA 4.0
<span class="int-own-work" lang="en">Own work</span>