From this list ... route no. 7 tonight!
Normal routing to avoid overnight engineering work:
1. Exeter, Taunton, Bristol TM‡, Bath, Swindon, Reading
2. Exeter, Taunton, Bristol TM, Bristol Parkway, Swindon, Reading
3. Exeter, Taunton, Bristol, Bath, Newbury, Reading
4. Exeter, Taunton, Westbury / Westbury avoider, Newbury, Reading
5. Exeter, Taunton, Westbury, Melksham, Swindon, Reading
6. Exeter, Yeovil, Castle Cary, Westbury / Westbury avoider, Newbury, Reading
7. Exeter, Yeovil, Castle Cary, Westbury, Melksham, Swindon, Reading
Houston, we have a problem
8. Exeter, Taunton, Westbury, Bath, Bristol TM (loco onto other end of stock), Bath, Chippenham, Swindon, Reading
9. Exeter, Yeovil, Castle Cary, Westbury , Bath, Bristol TM (loco onto other end of stock), Bath, Chippenham, Swindon, Reading
10. Exeter, Taunton, Westbury, Bath, Bristol Parkway, Swindon, Reading
11. Exeter, Yeovil, Castle Cary, Westbury , Bath, Bristol Parkway, Swindon, Reading
12. Exeter, Taunton, Westbury, Melksham, Chippenham, Bristol TM (loco onto other end of stock), Bristol Parkway, Swindon, Reading
13. Exeter, Taunton, Westbury, Melksham, Chippenham, Bristol Parkway, Swindon, Reading
14. Exeter, Yeovil, Castle Cary, Westbury , Melksham, Chippenham, Bristol TM (loco onto other end of stock), Bristol Parkway, Swindon, Reading
15. Exeter, Yeovil, Castle Cary, Westbury , Melksham, Chippenham, Bristol Parkway, Swindon, Reading
All the above should be possible without having to provide additional Traincrew for route knowledge. At one stage it would also have been possible to send the train into London Waterloo rather than Paddington via either Acton or from Reading.