Formula too long for drop down list data validation???

Instead you could devise a short table to VLOOKUP, and use the INDIRECT result.

Let's say somewhere you have on Y1:Y12 = months, and Z1:Z12 = Januaryweek, Febuaryweek, etc

=INDIRECT(VLOOKUP(G2,Y1:Z12,2,0))

This will look up the month from G2, associate it with the monthweek list name, and output correctly.

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Thanks.

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