I have a Vlookup formula that works, but now I want to have it read a date from a cell in the current worksheet, and make that date/string? part of the full path filename telling Vlookup where to look (in another workbook).
The date is in cell B1 and I have named B1 "Date". It will never be today's date, it will always be a previous date. The filename is (using yesterday's date as an example)

Summary Report_20100309.xlsx

This is what I have:

=VLOOKUP(M4,'[C:\2021\FILES\03\[Summary Report_&TEXT($Date)&.xlsx]Summary]'!$A:$D,4,0)

How do I get it to recognize the string in B1 and make it part of the filename? Thank you!