New answers tagged localrepository
It looks like your repository mirrors only amd64 packages, but your system wants both amd64 and i386 packages. Just add deb-i386 lines similar to the deb-amd64 ones you already have, and sync the mirror again.
Yes, unless you change distro. Packages might be removed when moving to Trusty to Xenial (for example). Note that usually no new software is added to the repo on the same distro (or maybe on point-version, like 14.04.4), but just the new versions of software already there.
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