Can cp or rsync copy all files modified after a certain date?
I don't want to lose data by losing my flashdrive in the snow the day before I fly home again, so I'm thinking I'll take nightly backups of modifications on my fone, which can then be applied to a complete backup made immediately prior to leaving, if necessary.

🤔 And do the same from fone to flashdrive, if it's not a massive headache to prevent that being recursive.