How long in capsule

DD is on the small side was born 2.6kg and now at 4mths is 5.7kg. I've just been investigating the weight she needs to be until she stops going in the capsule, this is 8kg. According to the growth chart she won't reach 8kg until she is 9mths (she is tracking along the 25th%). I've also read the alternative is a length of 70cm, again according to the growth chart she won't reach that until 10mths. Should bI e waiting this long or change her when she has good head control?

i hace just had a session at my mothers group fron kidsafe and they say to keep the rear facing for as long as poss and in the capsules until they reach the 8kg or the length so i would say you have lucked out and can keep your DD in the capsule for a long time...