You didn't understand my question I guess

I am looking for a formula in cell I1 and I2

First of all there are two records.

Row1:
There are two dates for May and 9th May is the first date = 9.
There are two dates for Jun and 1st June is the first date = 1.
There are three dates for July and 13th July is the first date = 13.
Therefore the max value is 13 (out of 9 1 and 13) so I1 will contain 13

Row2:
There is one date for May and 13th May is the first date = 13.
There are three dates for Jun and 6th June is the first date = 6.
There are three dates for July and 1st July is the first date = 1.
Therefore the max value is 13 (out of 13 6 and 1) so I1 will contain 13

Maxi