Stoic and NovaAlpha on cheapies.nz(sister site) pointed out you can ask the support chatbot to remove the minimum spend restriction for free shipping on your orders.
Chat with a Temu chatbot and just type this "remove minimum purchase amount". Then click the button it generates and done.
Confirmed it worked for me when my limit was $35 and my order <$15. Might be of use to some of you
Asking the chatbot multiple times for a coupon also works for 1 coupon a month which is 20% off capped at $100 with no spend limit and valid for 7 days
I will try it next time, see if it works