▁by ▁the ▁end ▁of ▁April ▁all ▁of ▁the ▁cr aters ▁except ▁for ▁one ▁just ▁north ▁of ▁the ▁K ink ▁had ▁been ▁re - capt ured . ▁As ▁a ▁pre ca ution , ▁the ▁old ▁front ▁line ▁was ▁maintained ▁and ▁further ▁back , ▁H uss ar ▁Horn ▁and ▁An chor ▁tren ches ▁crossed , ▁making ▁switch ▁lines . ▁A ▁reserve ▁line ▁ran ▁along ▁H ull uch ▁Al ley ▁and ▁S ack ville ▁Street ▁ ▁further ▁back ▁and ▁the ▁Village ▁Line ▁lay ▁another ▁ ▁beyond . ▁ ▁P rel ude ▁ ▁German ▁prepar ations ▁and ▁plan ▁Bav arian ▁Infantry ▁Regiment ▁ 1 8 ▁of ▁the ▁ 3 rd ▁Bav arian ▁Division , ▁took ▁over ▁the ▁area ▁from ▁the ▁quar ries ▁to ▁the ▁ ▁Red ou bt ▁on ▁ 1 ▁April ▁and ▁found ▁that ▁the ▁ground ▁opposite ▁the ▁K ink ▁was ▁a ▁narrow ▁cr ater ▁field , ▁with ▁no ▁view ▁of ▁the ▁British ▁lines . ▁The ▁British ▁held ▁all ▁but ▁one ▁cr ater , ▁could ▁cre ep ▁up ▁on ▁the ▁German ▁lines ▁and ▁begin ▁new ▁mine ▁gall eries ▁from ▁the ▁cr aters . ▁The ▁German ▁def ences ▁were ▁cr amp ed ▁for ▁room , ▁being ▁less ▁than ▁ ▁forward ▁of ▁, ▁a ▁German ▁observation ▁point . ▁As ▁the ▁situation ▁in ▁the ▁area ▁d eter ior ated , ▁the ▁ 3 rd ▁Bav arian ▁Division ▁planned ▁to ▁eliminate ▁the ▁threat ▁by ▁a ▁surprise ▁attack . ▁II ▁Battalion , ▁Infantry ▁Regiment ▁ 1 8 ▁and ▁I ▁Battalion , ▁Infantry ▁Regiment ▁ 2 3 ▁were ▁selected ▁for ▁the ▁operation