I honestly can't work out the round up problem (it wasn't called a drift until the London imigrants flooded the area). The cycle event used the two main road entrances, which no sane person would ever run the round up through. To start with they couldn't get the horses there unless they rode them over cattle grids. In previous years the round ups are done on weekdays and not weekends to minimise the risk (it is bloody scary to be caught in the middle of a round up, I've experianced this, it is the only time I have ever permitted my dogs to bark at the ponies and I seriously gave the riders a piece of my mind).
Brockenhurst is now mostly populated by moneyed imigrants, who want the "rural" life, and I believe it is these people who are making all the fuss.
UK cycle events booked the event in 2012, the verderers informed them of the round up 23rd September 2013.