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You're getting that error because each BRI interface can only have 1 entry in the DIAL PLAN (rather than 2 - one for each B-channel). So your IN#ACCEPT for each BRI will have both numbers, and your SPID LIST will also have 2 Phone Numbers and 2 SPIDs. (Each with CALLS set to 1.)
Also, in the SPID LIST, the PHONE # is a maximum of 7 digits - so leave the area code off for the PHONE #. Your SPID looks fine.
The IN#ACCEPT needs to be configured as well, so the ATLAS knows to which BRI to send calls. This will be the phone number presented by the Telco on an inbound call. (It could be 10 digits, 7 digits, or even 4 digits.) If it is less than 7 digits, then the PHONE # in the SPID LIST will need to be changed to be the same number of digits as the IN#ACCEPT (remember it will never be more than 7 digits).
For your final question, if the Network Term is also BRIs then it will be configured similarly - but the Telco will give you the SPIDS and LDNS and generally the OUT#ACCEPT will be "$" which is our wild-card to allow any number (since you are calling out to the PSTN and will not be a specific number for every call).
Hope this answers your questions,