If you have a Garmin head unit you might consider leveraging Xert Segment Hunter (XSH).
Here’s a recent post about it – Segment hunter - no segments loaded
This assumes the TT course can be identified as a start/end segment on Strava.
XSH isn’t so much a pacing tool but rather an MPA management tool.
It should help you from starting out too hard and keep you within range of what you’re capable of maintaining throughout the course.