The campaign might not want to commit Hillary to a campaign appearance in a locked-down state like California when an appearance in Colorado or Iowa might be more strategically important.
I hope, for the good of the country, that the absence of scheduled events is due to health concerns and the American electorate realizes that we can't elect a President with limited ability to serve and who's likely to have to turn the office over to that lunatic, Tim Kaine.
Exactly this. It's pretty much the same for candidates for just about any elected office.