Off road to Brighton

Ha that's cruel advice for someone on 28s

Oh yeah 😅
OP will be fine on 40 though

Did the BHF route with @psg1ben the other year some small sections were a bit much for a CX bike but generally the route was good. There was a very tough rocky climb before going over the top into Eastbourne.

as if you didn't have enough options here's my route. All doable on a gravel bike.

https://www.strava.com/routes/26629344

takes in Ranmore Common, Leith, Holmbury & Pitch Hill, Cranleigh onto Downs Link and then up and over the aptly named Fulking Hill and Devil's Dyke

EDIT: and here's the obligatory video so you can see what the terrain is like. Me and one buddy were on our 26" MTB but only cos I didn't own a gravel bike last time I rode this route.

Other buddy is on gravel; an Open UP

https://www.youtube.com/watch?v=cvEbD0XkNQ4

how did it go? thinking of riding it at some point

It was great. A good mix of fast gravel and more technical paths, the roads are mostly quiet. Some of the paths were overgrown, which was fun but slowed us down. The climb at the end over the beacon is short but brutal, with what felt like 20% gradients, all off road. The ride and views at the top are amazing though...
Oh, we got told off by a golfer at some point as apparently we weren't allowed through. Not sure it's true, we went anyway.
A fiew pics on my Strava..

https://strava.app.link/Ka7fIxyvQqb