Ermm - the Examiner is not permitted to give you the route the day before the Skill Test...... You're supposed to get it after the introductory pre-test brief and then to have around 1 hr to plan before you give your pre-flight brief.
The route you mention should be 'uninterrupted' on the first leg. On the second (from Rednal) you should expect the diversion after about 5 or 10 minutes - you certainly shouldn't expect to fly much further than Stafford before being given the diversion.
Good luck with the Wx - The vis. should be >6 km generally, but not <3000m at any stage. Cloud? For you nav route, generally >1500' agl but not <1100'; for the GH not <1500' (not <2500' for stalling). Wind velocity < 30KT, and crosswind < aeroplane limits. If it's worse than this - DO NOT FLY until you've asked your FE to refer to the FE Handbook, page A2-1, for these recommended Wx limits!
Hope it goes OK!!