Both - you can fire road it all or you can avoid a lot of the fire road and ride the trail
https://www.strava.com/segments/5244753?filter=overallI think I managed 5 full and 3 partial in one day but was fit at the time. Maybe could have done one more.
You can get uplifts - pay as you go - on the day and in the Afternoon you can usually get on the bus that way no probs.
https://www.bikeparkwales.com/upliftQuote:
Depending on availability (riders with a day pass will always take priority) you may be able to fill spaces on the uplift adhoc on a single trip basis, you can buy cards from the reception desk that will allow you 1-5 rides at a charge of £4 per ride. These cards are non refundable but can be transferred to other riders and are valid for one year from date of purchase. Alternatively you can pay the driver £5 cash per ride.