Upgrade - Trainee to track

[ForZiE23]

Hello Guys,
New on here and somewhat new to marshalling too (Started and beginning of season this year). I have done 7 sessions on incident now so a way from upgrade but a little confused on requirements. I "think" i heard in training but cannot find anything to double confirm this you need 15 signatures before assessment on upgrade of which X need to be incident and X flagging.

Now in the blue book it say min 2 of one sort so can do 13 track and 2 flagging, the assessment. BUT i have some feeling its changed and need to do at least 5 of each in this 15 required? All though not in any rush to really upgrade i am thinking to balance my signs do i need to get some flagging in now otherwise will not have requirements when need them next year. Looking on MSA website i cannot see any chances from this min 2 in either way.

Thank you for your help in advance