wˈʌns ɐn ˈɑːpoːɹd ɪz ɡˈɪvən, ðə sˌɪtʃuːˈeɪʃən mˈeɪ tʃˈeɪndʒ bᵻfˌoːɹ ðə mˈɪʃən bɪɡˈɪnz, ɔːɹ, dˈʊɹɹɪŋ ðɪ ˌɑːpɚɹˈeɪʃən ðə sˌɪtʃuːˈeɪʃən mˈeɪ tʃˈeɪndʒ sˌoʊ ðætðə bˈeɪs ˈɔːɹdɚ mˈʌst biː mˈɑːdᵻfˌaɪd.
Once an OPORD is given, the situation may change before the mission begins, or, during the operation the situation may change so that the base order must be modified.