P1 Rest OCtet and Packet Page Indication

In the case of P1 rest Octet filling , how does the mobile decide whether the PactePageIndication2 is presebt or not ? Is it based on the Priority2 presence ?
=============================
< P1 Rest Octets > ::=
{L I H < NLN(PCH) : bit (2) > < NLN status(PCH) : bit >}
{L I H < Priority1 ::= Priority >}
{L I H < Priority2 ::= Priority >}
{L | H < Group Call information >}
< Packet Page Indication 1 : {L | H} >
< Packet Page Indication 2 : {L | H} >
{ null | L — Receiver compatible with earlier release
| H — Additions in Release 6 :
{ 0 | 1
=================================
The Packet Page Indication i field relates to Mobile Identity i (i = 1, 2) and indicates the kind of paging procedure associated with the mobile station identity. If the identity is not IMSI the Packet Page Indication has no meaning and is ignored.
L paging procedure for RR connection establishment;
H packet paging procedure.
=================================
Regards,
Gokul