Copy Millions of Records from one table to another with the same schema, in the same database
How about keeping all the incremental data inside the inactive table until the end of the day, then load it into active and truncate inactive? Your view could reference both tables using a UNION ALL, that way you aren't switching between the two tables.

You could use partition swapping with the same method. You'd partition both tables, load inactive until 11 PM at night, then swap inactive's loaded partition into active. Your view would still need to reference both tables. This way, you have no downtime for loading besides the time it takes to initially import the file, and incremental files should be loading into an empty table every day.