[Opendnssec-user] ods2 signed zone ignores specified Serial format (unixtime), publishes RRSIG SOA with 'datecounter' ?

[PGNet Dev]

In signing my zone with ods2, using (atm) 'lab' policy, where

	cat kasp.xml
	    <Policy name="lab">
	    ...
	        <Zone>
	            <PropagationDelay>PT300S</PropagationDelay>
	            <SOA>
	                <TTL>PT300S</TTL>
	                <Minimum>PT300S</Minimum>
	                <Serial>unixtime</Serial>
	            </SOA>
	        </Zone>
	    ...

note that Serial == unixtime is specified.

but, the singed zone changes the RRSIG serial to 'datecounter' (cref: 
https://www.opendnssec.org/documentation/using-opendnssec/) format

	egrep -i "serial|SOA" /var/opendnssec/signed/example.info
		example.info.     300     IN      SOA     dns.example.com. 
soacontact.example.com. 1482169654 7200 1800 604800 300
		example.info.     300     IN      RRSIG   SOA 8 2 300 20161219184751 
20161219164734 38544 example.info. pib...U=

shouldn't the 'unixtime' format be used consistently/unchanged in the 
RRSIG SOA record as well?