If controller asks you to report a certain phase of flight that happens in the (near) future (position, level, distance etc), the best answer is "WILCO" - suits perfectly for most of the occasions. No need for long readbacks.
A Finnish example:
ATC: "Cleared to XYZ control zone ("via [FIX name] / flight plan route / etc"), report control zone / [FIX name] inbound."
PILOT (what I'd like to hear): "Cleared to XYZ control zone via..., AB-CDE, wilco."
JEP:
Don't know much about your procedures but here flying in controlled airspace is prohibited without a clearance, so we give clearances by using the phrase "cleared"
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