Done that route a couple of times. Best is down the M5 turn off at Gloucester onto A417 through Swindon, left onto M4 and then turn off onto A 38 past Newbury onto M3 and then A31. It is a longer journey, but less stress.
The other way is again off at A417 near Gloucester, but instead of picking up M4 you across over the M4 onto A345 towards Salisbury and then onto Poole. Slow and if you get stuck behind a tractor even slower.
Either way it is over 3 hours from Worcester to Poole.
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