ladyofastolat | Walking dilemma

My boots have given me hundreds of miles of trouble-free walking. However, two weeks ago, in the latter half of the longest walk I've ever done (22 miles), my boots started pressing painfully on my right ankle bone and, to a lesser extent, my left Achilles tendon. I didn't walk for two weeks after that, but this weekend, these places hurt right from the start - not enough to stop me walking, but enough to make decreasingly enjoyable as the day went on. It's not a skin irritation thing; it feels more like a bruise, if anything.

Walk the Wight is in 4 weeks, so now my dilemma is: do I stop walking for these four weeks to let the sore bits heal, or do I carry on regardless, since stopping would undo all the benefits of practising, and would cause worse problems on the day, due to over straining unprepared muscles? I'm tending towards the latter, because a tender ankle bone merely hurts, but isn't likely to cause real damage, whereas walking 26.5 miles without preparation could do lasting damage.

It's too close to the event to walk in new boots, although new boots might be the longterm answer. Also, I can't do long walks not in boots, since I need the ankle support which stops me walking on the insides of my feet, which has bad results for knees and hips. This I have learnt.