milliseconds in gpx timestamps result in 'Call to a member function getTimestamp() on boolean' with php 5.6.29

A gpx file with timestamps including milliseconds, e.g. <time>2017-01-07T14:20:35.567Z</time> , will result in a php error

Call to a member function getTimestamp() on boolean at /nextcloud/apps/gpxpod/controller/pagecontroller.php#536.

(For example, the android app Locus Map exports tracks with such timestamps...)

System Info

• Nextcloud 10.0.2
• PHP 5.6.29
• Linux based shared-hosting

Please let me know if I can provide any further information.