Adding a structured workout to a race route after finalized race?

Hello!

I plan to participate in a time based climb race, and will likely not finalize the climb route within the time of the race. I wonder if it is possible to add a structred workout to the same route as I am on after the race, in order to finalize the route while doing a structured work out? This means that I would do two “activities” within one; First the scheduled race, and after the race is over a structured workout. I’d be grateful to know if anyone knows if this works (and doesn’t affect the race result)?

Thank you in advance!

Kind regards,
Sofia