Targeted the dark spot imaged by Phil Miles (Queensland Australia) March 24th, 31st and April 1st.
A quick and rough drift calc gave me a drift of approx -11.5 deg/day. Based on that I targeted it April 4th where my predicted L3 was 342. I measure the dark spot from my April 4th data to be at approx Lat 64.3 L3 345.6.
I have the dark spot close to the CM in the R channel in consecutive R data sets 24 minutes apart.
Have attached the two R channel data sets with the dark spot along with an animation of that data. Also note there appears to be a large scale bright feature in the EZ that is well seen in the animation. I have uploaded all data from April 4th to PVOL and ALPO Japan.
Note; the seeing was good for the capture of this data but the transparency was poor with quite an amount of haze which dropped the signal by about 30%. This spot must be quite bright to still be resolved with such a reduction in signal strength.