How are you feeling about how his cycles are going at the moment?
Would you feel comfortable holding a little longer?
On TR you would hold for a week in green (ie normal numbers 50-80 on human meter), or a drop below 50, but of course with dry in the picture you aren't following TR, as a prerequisite is to be on a LC wet diet.
The longer he spends in green the more healing time for the Beta cells, which can lead to a stronger remission. But with dry in the picture, I don't know if it would be wise to hold for a week in green.
His cycles are looking great but this is now just his 4th cycle on 0.5u, and some of those numbers in the 50's you got in earlier cycles might well have still been influenced by the depot. So it would be interesting to see if he still holds his own, today and tonight before taking him down. I am just not sure how long you should wait, purely because of the dry food (YA)