Read the following USCIS new policy on the biometrics collection for reentry permit (I highlight the red color words which are what you are concerning) from this website;
http://www.uscis.gov/archive/archive-news/uscis-biometric-changes-re-entry-permits-and-refugee-travel-documents
Q. I am a Lawful Permanent Resident (LPR) who will be out of the US for more than 1 year? What documents will I need to return to the US?
A. To reenter the U.S. an LPR normally needs to present his or her green card (Permanent Resident Card, Form I-551). A reentry permit is needed for reentry from absences outside the U.S. that are greater than one year but less than two years in duration. Thus, if an LPR anticipates remaining outside the U.S. for longer than one year, he/she will need to apply for a reentry permit while he or she is in the U.S. See 8 C.F.R. § 223.2(b)(1)(Re-entry permit may be approved IF filed by a person who is in the U.S. at the time of application)(emphasis added). An application is not complete until an individual has provided his or her fingerprints and photograph (i.e., biometrics). The newly revised I-131 instructions also provide procedures for requesting an expedited ASC appointment for biometrics collection and for requesting expedited delivery of a travel document, where needed. USCIS believes that the majority of LPRs who live abroad will be able to re-enter the U.S. using their Permanent Resident Cards. Those LPRs who currently live abroad, but who know that when they return to the U.S. they will need to apply for a Re-entry Permit because they plan to leave the U.S. again for more than a year and will need the permit to re-enter the next time they come to the U.S., USCIS encourages these LPRs to anticipate their need for the Re-entry Permit sufficiently in advance of their travel and, if necessary, to follow the procedures for obtaining an expedited ASC appointment where absolutely necessary. If the LPR departs from the U.S while the I-131 is pending, but before biometrics are taken, then the adjudication of the I-131 re-entry permit application will not be affected as long as the applicant returns to the U.S. to attend the biometrics appointment before the first year of foreign travel has ended. In such case, the LPR could apply for reentry to the U.S. using only his or her I-551 Permanent Resident Card if he has been absent for less than one year. We further note that if it is necessary, the LPR may make arrangements to have his Re-entry Permit delivered to him through a U.S. consulate or a USCIS office abroad. 8 C.F.R. 223.2(f).
