Hide Quotes when Flat Rate Shipping Method is present

Hi,
I am hoping this plugin is still supported as it appears to be the only plugin I can find that actually works.

I am using my Transdirect account login for the Shipping Options and it is working better than expected. (Unlike the actual Transdirect Plugin which is completely useless).

The only issue I am facing is that I have set up Flat Rate Shipping in Woo Commerce. While the Ozpost plugin shows the Flat Rate cost which is awesome, it also shows the Transdirect shipping costs, even when a Flat Rate applies.

In short, what I need to do is hide the Transdirect quotes, when Flat Rate Shipping is used as a Shipping Method. If Flat Rate does not apply, then I would like the Ozpost plugin to kick in with the Transdirect quote.

Any help would be appreciated.
Thanks