Micro Updates triggering Yum Updates?

[Red Paint]

Hello,

We've got micro-updates set to install automatically, that's fine and quite happy with that. Unfortunately the most recent micro-updates have triggered yum updates/upgrades and this has caused us lots of issues the most serious of which was a forced update to PHP5.4 from 5.3 as the repo we used changed to 5.4.

I understand that all eventualities can't be considered but why is this yum upgrade being triggered and how can it be stopped?

Thanks