Why is BRCA nat at RHR not on the dirt track?

[DAVO]

Hi is there any plans to run a BRCA national on the dirt track at Robin Hood.Just seems daft to run on the astro when there is a dirt track next to it. I have nothing against astro tracks and think there great but dirt/ clay tracks a few and far between in the UK. It would be good practice for our national drivers for when they race against the the rest of Europe/ world.i just wondered why the BRCA team did not choose (if they had the choice) to run a rnd on the clay track
Thanks Davey