Calling all armchair generals! Boudica's Last Stand.

[Nathan Ross]

it seems that the actual civilians in those places who were slaughtered would be less than 20,000

I agee - perhaps considerably fewer. But with a citizen population that small, even a few thousand deaths would have had a great impact.

the quickest way to London would have been via Watling Street and to St Albans, a Roman City that had to be protected.

I agree with Michael that Paulinus would first have directed his march towards Colchester, intending to link up with Cerialis on the way. Only after abandoning London would he fall back on St Albans, where supplies would remain intact.

The strategic map of the campaign, considering only Roman movements, would look like this:

   

(Original map from here)

I would go for third week in September to allow for the arrival of re-inforcements from Germany and the replacement for Catus.

Possibly, at a push, but probably requiring a bit too much motu propere from Paulinus, and from his intended reinforcements from the west!