I tried this in different ways but I'm unable to reproduce it. This is what I tried.
Added hair to an object, added Edit Guides and deleted to guides, save and reload.
Added hair to an object, reduce the guide amount to 0, add some guides with the Plant Guides tool, add a second Edit Guides and delete some guides, save and reload.
Repeated the second tests but instead of the Plant Guides tool I used the Create brush to add guides.
In all the three tests the hair object is fine after reloading the scene. There is a new build from 23 hours ago, try that one and let me know how it goes.
Jeordanis Figuereo (Product Designer. EPHERE Inc.)