Indicates the start of the time range for which to retrieve offline payments, in RFC 3339
format for timestamps. The range is determined using the
offline_payment_details.client_created_at
field for each Payment. If set, payments without a
value set in offline_payment_details.client_created_at
will not be returned.
Default: The current time.
Examples for January 25th, 2020 6:25:34pm Pacific Standard Time:
UTC: 2020-01-26T02:25:34Z
Pacific Standard Time with UTC offset: 2020-01-25T18:25:34-08:00