[Bug or feature?] GGR stats decreasing

The server I play on recently got updated to Minecraft 1.25 with IC² and RailCraft. Since then I've noticed a decrease in stats of some of my Agriculture plants. Slowly but decreasing for sure.

It happened several times among the plants which I use to boost GGR stats. I keep a record of the stats for every plant on a sign right behind it.

Is this a new feature, an old one (which then I haven't noticed before today) or is it a bug?

If it's a feature, I'm afraid my days as a gardener is over. My goal was to create some 20-25 GGR plants, and then make a nice little area, where I could collect the loot when needed.
If the stats are randomly decreasing over time, I see no point in this as it would take too much time to keep them going.

Quote from RichardG

Using cropmatrons loaded with weed-ex to keep your crops?

I have done that.. At least with my main booster area. Weed-ex and Hydration cells all the time. Fertilizer are not always available.

Are the plants supposed to decrease if their not being taken care of?

Quote from RichardG

Then it's a (don't tell anyone) downside to automation.

Too much Weed-ex, I guess?

Wait, you don't have to answer. I'll try with just Hydration cells and Fertalizer from now on. If it happens again, I declare the Crop-matron useless and a waste of time.