STP pubsub current time uses .z.p

In the segmented tickerplant pubsub code, in the functions `.stpps.upd.chained`, `.stpps.zts.def`, and `.stpps.zts.chained` current time is defined by `.z.p`. 
Instead of `.z.p`, could this be changed to use `.proc.cp[]`? It is causing some issues using .z.p as the definition