One of the provisions which was intended to be included in this amendment was the specification that all aircraft being operated under the instrument flight rules and cleared "on top" would be operated at altitudes prescribed for VFR flight. While such a provision was included in the amendment, it was inadvertently placed in § 60,hi|. (a) which is entitled "Within controlled airspace," This arrangement technically limits the applicability of this provision to flights within controlled airspace.

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... Contrary to the intent, this would require a flight operating "on top" on an IFR flight plan to change altitude as it transited from or to uncontrolled airspace.