As I read your question, it seems to me that you think the attorney is somehow in charge of the estate and that he is responsible to produce the most recent will or trust. Therefore, if he is not updated, he could err in this duty. This is totally wrong.
Your new attorney has no duty to inform the old attorney of anything. The attorney who drafted your documents is not in charge of anything -- he just drafted documents. Because he never has any way of knowing that you didn't write new documents the following day, he is not expected to hold the most recent will or trust.
If you think it would clear up confusion, you can inform the prior attorney that the old will is no longer useful and have him destroy it.
I agree with my colleagues. The representation of the first attorney essentially ENDS, once your estate planning documents are established. There is nothing that prevents you from using another attorney to update and amend your documents, or to create an entirely new estate plan. There is no duty to inform the initial attorney. Of course, if your initial attorney has retained all of your original documents, you will want to retrieve them.
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