NFHS delay progression

[Scrapper1]

In FED rules, does a team get more than one delay warning per match? If Team A gets a delay warning in set 1 and then delays the match in set 2, does that get a delay penalty? I'm pretty sure the answer is yes, but my partner today was pretty adamant that the delay in set 2 is another warning.

Here's the exact scenario. Team A could NOT figure out how to make a legal libero replacement. After my partner checks the lineups prior to the start of set 1, the libero enters the court along the end line. I saw it and purposely ignored it, thinking that I didn't want to start the match with a verbal warning for such a minor thing. In the second set, the two middles do a "double replacement" through the substitution zone. My partner sees it and give me gesture that said "Whatever, let's just move on". In the third set, the double replacement happens after I beckon for serve. Now, we're both a little frustrated by this and he gives them their verbal warning. Later in the third set, something happens that I didn't see and he requests the unnecessary delay, which I give. In the fourth set, they AGAIN make the libero replacement after the beckon for serve.

I allow the serve to continue and Team A wins the point. My partner signals for another delay card, but when I pull out red, he's completely surprised. So he comes over to talk and since I wasn't 100% sure, we gave a second yellow.

So. . .

1) Is the yellow card the correct administration after multiple incorrect libero replacements?

2) If yes, would a subsequent incorrect replacement in a different set result in a delay PENALTY (red card) as I thought?

3) If yes, does the delay penalty result in a loss of rally and a "side out" for the non-offending team; or is it an administrative penalty (a point only, and no loss of service) like for illegal uniforms?

Thanks