This is one recent version of the F1/25. The race HQ for the F1 based courses is usually Tempsford Hall.

 The current version is similar:

COURSE F1/25 - 25 MILES (2008) Start Sheet text
START (GR 163539) on the B1043 approx. 1400 yards north of the Tempsford flyover;
150 yds south of Station Rd Tempsford, 7yds south of LP9.
Proceed south over small rab to join A1 southbound (CARE) to:-
TURN (2.99mls) at Sandy RAB and retrace on the A1 northbound over Black Cat RAB
TURN (15.20mls) at Buckden RAB and retrace southbound A1 over Black Cat RAB to:-
FINISH (GR163524) on the A1 at a layby approx 330 yds north of (i.e. before)
Tempsford flyover at a drain 32yds south of lamp post TE104.
Police Area s : Bedfordshire, Cambridgeshire
LOCAL REGULATIONS No. 1, 3 and 4 (page 13) apply.
DISTRICT INSTRUCTION (page 14) applies.
NOTE: No more than 2 officials cars should be parked in the Finish layby, i.e.
Timekeeper and one other

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