Metropolix handling when clocking externally with varying bpm

I’m clocking Metropolix from Making Sound Machines Stolperbeats, which isn’t precisely stable clocking. This got me thinking, what aspects of Metropolix will be different when clocking from unstable/varying clocks?

Will anything on a x1 time division be advanced only when a new pulse is received, or is there an internal clock derived from the external signal that might take precedent if a pulse is late? I’m assuming it could affect slide timing and cases with between beat time divisions, such as /3.