How to formulate lookup function?

I'm an excel newbie and I need a lookup formula that will return data on my cells.

I have a Data in columns A and B (about 45,000 rows)

Column A Header = Campaign
Column B Header = Date

my criteria in F52, and based on this criteria I need to return the previous date in F55 and the next 2 previous date in F56.

I attached a dummy workbook for reference.

Thanks!