Surface segments do not count against the continental limits - unless you actually travel on 5 (or more) inter-asian flights as part of the booking the purchase of additional segments is not required.

Note that surface segments DO count against the 16 segment total xONEx limit.

e.g. The following is valid as part of a xONEx and no additional segments need be purchased:

• -YVR-HKG-TPE-HKG,BKK-SIN,KUL-NRT,HKG-LHR-

However, in this example, the Intra Asian segments do use up 7 of the total 16 available.