Fruit nerd your P88 looks great nice healthy tree, mine has been in the ground 19months is also really healthy they really like it here.
I would be very cautious about pruning it especially topping it, a bit over 12months ago a storm broke off the top of my P88 so i cut it to make it a clean cut, anyway since then the tree has grown upside down, all the growth has gone to the top of the tree and the bottom of the tree is missing all the sap. All the top branches and laterals are nice and fat with lots of leaves which is not ideal you want the bottom part of the tree to have the thick laterals etc.
This is not the first time I have seen this, also some guys it hawaii noted similar when they topped their trees. In my case i didnt want to top it, it happened due to storm but im now very sceptical about topping my trees until they reach desired height.
Just my experience others may have found different