Guide keeps reverting to "To Be Announced"

I've seen scattered posts about this on more than a few sub-forums so i thought i'd start a dedicated thread about it here.

For the 5th time since the Rovi switchover back in Sept 2016, my Guide Data has disappeared and was replaced by "To Be Announced" on all channels. Before the Rovi upgrade, this never ever happened. The first TBA happened when my 2-tuner Premiere got the Rovi upgrade.

Yesterday morning (instance #5 now) my Premiere stopped recording my morning news on both tuners...

Guide keeps reverting to "To Be Announced"

Guide keeps reverting to "To Be Announced"