Are you staying in B&Bs or the camper van?
If it’s B&Bs, keep the plan loose – have in mind an “aiming point” of where you want to get to but be prepared to move it. If it’s a lovbely day, nice weather, tailwind and you’re all on good form you may want to push on by 25 miles or so. If it’s crap weather, you’ve had mechanicals etc, you may want to end the day earlier than planned so it’s useful to have the driver park up, find some suitable local accommodation and book it online there and then (booking.com is brilliant for this).
Saves you having a rigid plan and allows options for diverting etc.
Midges: if you stop for anything (puncture, photos, navigation) they can be on you in seconds and once on, they won’t shift until you kill them or they’ve eaten their fill. Riding fast and hoping the wind will blow them off doesn’t work!