After a run of poor post processing results I followed a piece of advice given to me by @TB_RTK, which I should have followed way earlier.
Delete your RTK post.ini file and build up your processing options again. This took me from 42% fix to over 90% fix. It took about 10 iterations as, once I had set the basics, I only changed one variable at a time. I recorded the percent fix/float/single for each solution. A painful process, but now my processing just uses the final configuration and I am getting good results.
Update to this dataset.
I just re-ran it using combined (forwarda and backwards) and continuous, rather than fix-and-hold. I think because my noise levels were good the combined method managed to fix the data at the start of the file. So now I get 98.7 % fix!
HOWEVER. I have been seeing an offset in my orthomosaics produced by PPK. I attributed it ti the SFM processing, but look at this…
One solution is the raw LLH file and the other the PPK .pos file. The base position in the RINEX header is different to the postion displayed on the screen after a base is established and yes the offset appears to be the same direction and magnitude as my orthomosaic offset. My reference points were collected in realtime (not post processed) and were all 1.1m west and 27cm South. Please Emlid, as a matter of urgency can you have a look at the code and see if an offset is sneaking in?