If you will discontinue the address and telephone number I would say it is a definite change requiring notice.
If there is an unauthorized transaction, the consumer needs to know who and where to contact. I would say that the OSC @ 205.8, 4 is explicit and the merger would not exempt the intent of this notification. The only time it wouldn't be needed is if you are not holding them to any liability. That isn't generally the case.
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AndyZ CRCM
My opinions are not necessarily my employers.
R+R-R=R+R
Rules and Regs minus Relationships equals Resentment and Rebellion. John Maxwell