The Update Activities page on Horizon Connectors combines with the Run (execution) log and together hits the 100-log limit on the UI. Gainsight Support has confirmed that Gainsight will store only the last 100 execution (Job runs and Update activities) in the UI and out of that the update activities will be displayed in this space.
If we have a few different Connector jobs running hourly, this leaves us with maybe 2-3 days of logs. Then we need to go to Support to find out what happened for anything older.