The withholding time is an additional procedure to the processing time. During this time the finance department must look into client's account details, transaction information, and limits, before the funds are credited into the wallet or transferred to their bank account.
As soon as we are notified about a transaction request, the withholding time is imposed for security reasons. The length of this process may vary depending on the number of wire transfers previously requested by a user, the amount, the currency, and the date requested. Usually, the first wire transfer often consumes the maximum withholding (up to 3 days for USD and 5 days for CAD wire transfer) on top of the processing time whereas the following deposits/withdrawals wire transfers can take less time. This will depend on your local financial institutions internal procedures/ business hours, or local regulation.
The processing time; however, is related to the transaction process regarding the moment the wire request is made, the senders' bank executing the payment to the other end institution, and informing the receiver (Coinfiled) that there's a payment on hold.
Please check this link for full information: Fees and Processing Time