Hi,

I made a small tool for visualizing the changes in the gene symbols. It can be accessed here.

And have a small write-up about how it works here.

In short, it works by:

Creating a git repository.
Flatten the tables to the files:
    HGNC IDs as the subdirectories, columns as file names and the rows as the data in the files.
Commit and tag the month.
Repeat steps 2 and 3 for every month.
Query the repository for the given symbol.
Make a heatmap from the results.

Resulting heatmap looks like this: