A habit you might like to consider is to make one global variable
unsigned long currentMillis;
and set it at the top of the loop() function
void loop() {
currentMillis = millis();
and use that everywhere instead of new variables taking their value from another call to millis().
I've always found currenMillis to be pretentious and annoying, I've gone with now since forever.
unsigned long now;
void loop() {
now = millis();
My sketches usually have one call to millis() and between zero and two calls to delay(), almost certainly all done with delay by the time I'm out of setup().
a7