請教大家HI返簽問題

H1下周準備去TIJUANA返簽,領館要求帶A complete copy of I-129 petition completed by employer and filed with D.H.S including all supporting documents that were presented. (3 copies for Blanket L, at least one must have an original signature),
1,這是指我兩年前RENEW我的H1時交的老的I-129複印件,還是我要新填一份呢?
2,3 copies for Blanket L, at least one must have an original signature這是什麽意思啊,隨便還要我老板再簽字啊
3,我H1今年第6年,年底到期,不是敏感專業,風險大不大?
謝謝!!