Heart Rate Zones wildly different 5 days apart?

My heart rate zones are completely different between these two runs, despite the runs only being 5 days apart. I haven’t changed any settings, my zones are based on %LTHR. Does this change in Running Lactate Threshold really affect the zones so much?

Picture 1 is a run from 22nd February, Picture 2 is a run from 27th February (today)

Any help or advice would be appreciated.