It was the "Sessions Statistics and Battle Results". I did try the "backup session cache" check box but when I played one game, no session statistics appeared. The "play one game for session statistics to appear" display remained as if I had not played a game yet. I tried reloading mod pack 55 with the "PMOD stats extra by SOLO" mod and that retained the stats from the previous game I played today checking the "backup session stats ...." box.
Recap: 1. All games played with mod pack version ...55, reloaded for each game
2. Game 1, played with PMOD, no check mark in backup session stats, stats displayed after first battle, log out
3. Game 2, played with PMOD, check mark in backup session stats, stats retained from game 1 in display after first battle, log out
4. Game 3, played with "Session stats and Battle Results", no check mark in backup session stats, stats display after first game, log out.
5. Game 4, played with "Session stats and Battle Results", check mark in backup session stats, no stats displayed after first game, log out.