HDM 17. Windows 10 (20H2, fully updated as of 12/7/20).

I set up a backup with scheduling as follows:

Every day at 12:00PM
Chain of 1 Full followed by 6 incrementals
Retain 2 full chains

When I relaunch the app, I see:

Every day at 12:00PM
Chain of 1 full followed by 2 incrementals
Retain all chains forever

Just tried it again (after a few days of trying repeatedly to set the desired config). This time it shows:
Every day at 12:00PM
Chain of 1 full followed by 3 incrementals
Retain all chains forever.

I don't know if this would be significant but, when I launch the app, Windows security pops up a dialog asking me to confirm that I want to let the app make changes. I've tried launching the app "as an administrator" but this makes no difference.

Anyone have an idea what's going on here? Thanks,

Barry