AS2 in wm 6.5 and upgarding to higher version

We are currently using 6.5 and partner is requiring FTP or AS2. We will be upgrading to 7.1 or greater this year. Since we are process of phasing out FTP protocal from our company and we have not done AS2, questions are

  1. How difficult would be implement AS2 in 6.5 using EDIINT/send service and port over to 7.1?

  2. Is it true in 7.1 AS2 will be a dropdown protocal in delivery method in TN/My webMethods? Is it easier to implement AS2 in 7.1 version that 6.5?

Trying to weigh out the possiblites and effort to either implement FTP for now and do AS2 after upgrade or do AS2 now in 6.5 and port over to 7.1 when upgrading.

Thank you