Trusts and SubTrusts

My father passed away recently. I have discussed this in another topic. He has 2 banks accounts (a checking and savings) in his Trust’s name. They under his Social Security number because before he died the Trust was Revokable but now that he has passed way it is Irrevocable. I am supposed to meet with his lawyer today. He is creating SubTrusts for 2 of the Beneficiaries. He is going to give me 3 new Tax ID’s, one Tax ID is to replace his Social Security number for his main Trust bank accounts, and Tax ID’s for the 2 new SubTrusts. As far as the main Trust I am not sure if the bank will keep the same account numbers for the checking and savings accounts now that his Social Number will no longer used or if the bank will create 2 new account numbers for the new Tax ID. My guess is the later. As far as opening up new SubTrust bank accounts, I want to be sure that when I move money from the Trust bank accounts to the SubTrust bank accounts for the beneficiaries that nothing is done wrong so that it will be a Red Flag to the IRS and they will try to tax it as income. To prevent this can this movement of money be accounted for on 1041 forms for the main Trust or SubTrusts so the IRS won’t try to tax it? If not, how would they know not to?