Every single day! We have a script that creates a Google base compliant xml file. It's uploaded with a cron job. We also have a backup .txt file that we manually upload just in case the CRON didn't work.
Did you update your feed to take in to account the new rules for Google shopping? I actually dropped my feed rather than go through the hassle of meeting their new requirements. The new rules went in to place way back in September, but their enforcement roll out has been very slow. If you didn't keep up to date then it may just now be finding you.
Dad always said, if you are good at something, make sure they pay you for it.
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