Calculate the Date of an Item Based on the Date of a Similar Item in the Previous Month

Assuming that the expected result is "June Target Item 14", try:

Formula:

=INDEX(INDIRECT(TEXT(B4-1,"mmm")&"!E5:E49"),MATCH("*Target Item*",INDIRECT(TEXT(B4-1,"mmm")&"!E5:E49"),0))

Let us know if you have any questions.