I have a client needing books from Jan 2021 to date. Their bank has a 123 day transaction limit. If I manually enter pre-cut off, can I still connect the bank feed?

You have to ask the file or download it from the bank. Then you have to import it manually. Another option, utilize MT Online as a workaround. It is designed to import into any bank or credit card in QuickBooks Online, so there is no specific setting needed. 

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