Hard to answer ur question as it is more about the fit of your baby and some baby's are taller/bigger/neck muscle dev faster so can stop slightly earlier(5 months plus minus). If sweaty, what some people do is to only wear it at aircon places or slip a fan (the stroller type ones) on the shoulder strap. U could also place a thin Muslim cloth between the 2 of u to absorb the perspiration - will more comfortable. I think what u can consider if u don't mind is to get the insert second hand as there are pple selling on carousel - since a Tula is exp and why not use it longer right? Hopefully you Can work something out :)
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