I do think that once you've made them, you should wait a day for them to set firmly before using them. I made my January Rising lip tar yesterday but I thought they were too soft to use immediately, even after I put them in the freezer to harden up a bit; today though, they were firmer and easier to use.
For what it's worth, I think it will be easier to use a scale and candle method to melt the lipstick base, I found it a little fiddly to use a microwave since I had to be careful to ensure the lipstick base wouldn't boil.
Just so you can see how the color didn't change, here are swatches I did of the lipsticks.
I hope you found this post useful! I think this is such an easy way to make your lip tars more travel friendly.