BUG or intentional Reading plan quirk

Parts of the reading plan can be read out of sequence. I can mark an out of order reading completed on the home page but not in the resource itself.  Is this the intended behavior? On something like a mobile ed class isn't it reasonable to keep to the schedule on the required readings but do optional readings on a time available schedule? But still wanting to take advantage of the check-off capabilities of the reading plan?

Orthodox Bishop Alfeyev: "To be a theologian means to have experience of a personal encounter with God through prayer and worship."; Orthodox proverb: "We know where the Church is, we do not know where it is not."