1. Maybe link for download offline site version in zip archive or single html file
https://github.com/gildas-lormeau/SingleFile. HTML is better than pdf because of word wrap. If someone has nothing on disk and want fresh install then he can move earlier this offline site to smartphone disk and open offline with normal size and without long lines.
2. Another "idea of idea"

- more than one changes folder (changes1, changes2...5 or user specified), first day changes are saved to changes1, next day (week or ?) to changes2, if there is for example 5 cycles then sixth day changes from changes2 are moved to changes1 and changes2 is used to save, seventh day changes3 are moved to changes2 and changes3 is used to save session and so on. If this is good idea then problem can be with dat containers - it should have changes folder like for Unix file-systems (test if there is changes folder or old root tree) These changes1-5 would be like restore points for Windows.