Many of us were taking Lantus for years before we had access to any CGM like Libre and are here to tell the tale. Night time hypos are not nice but our bodies are pretty good at waking when we go low.
Whilst waiting for your replacement, maybe run your levels a little higher? Before gong to bed, you could aim for a BG of around 8mmol/l with no active bolus on board (no NovoRapid for about 4 hours beforehand).
I also recommend making sure you have at least one spare Libre at home. So when you apply your penultimate Libre from your stock, put in an order. This allows you to have a spare in case your previous Libre fails.
I do the same for insulin - put in an order when I am down to one cartridge in the box - and test strips - put in an order when I have one box of strips in my diabetes drawer.