Yup, very dependant on where you stop and how often. Also the main problem is if anyone is late. Most convoys I have been in plan in quite a lot of contingency for this, say stopping for 20-30mins at each stop to collect everyone. TBH you can normally make better progress than googlemaps suggests, so I find it best to base the time on that (to account for any unexpected hold ups), add in say 15-30mins for each stop and that should get you to Chester in time Think those coming from the South coast will be gettin up very early!