If you are planning on importing payments on to these Schedules, Importacular Classic needs a way to find the schedule in order to attach the payment. The payment process attempts to find a corresponding RG Schedule record. It does this by a number of methods.
1. The first record that it finds (this is ideal when you are sure that there is only one RG Schedule on a constituent)
2. By matching on the reference field
3. By matching on the reference number field
4. By matching on a gift attribute (this should be a text or number attribute).
For options 2,3 and 4, the identifier should be unique to that recurrence. For example if I decide to pay $10 each month then the RE Schedule record should have a unique id for that should also come through with the regular payments too.
We recommend option 4 and encourage users to create a Gift Text Attribute called something like 'Recurring Gift ID' and include a Gift Attribute mapping in your RE Schedule and RE Payment templates that look to attached the 'Recurring Gift ID' attribute with the appropriate attribute description (the unique identifier ID).
What do you do if you do not have a unique recurring id but may have more than one RG Schedule record on the constituent?
You may want to use the constituent id (or other id specific to the constituent) instead. You just need to make sure that if you terminate an older RG Schedule record that you also remove the constituent id from their reference field.