I'm going to give the podcast player a go on my commute home tonight to see if it tries to skip tracks. If it works then I'll probably just dump spotify. I've been looking for a reason to cancel on them for a while anyway because they have terrible support.
Things I'm going to try.
1. rebooted phone (done)
2. Reinstall spotify (in progress)
3. MFT master reset
4. Restore of phone