Question about cold snaps and seedlings

Question about cold snaps and seedlings

A week and a half ago a bunch of volunteer squash seedlings popped up in my garden. Last night a cold snap came through. This is a late March Texas cold snap so it's not QUITE freezing, but it's close, and there's frost predicted tonight and tomorrow morning before the temperature shoots back up to 70. I covered the most robust seedlings with plastic bottle halves and draped sheets over the bed. This morning it is cloudy, extremely windy, and cold, below 40. There's a slight chance of flurries before 1pm, but I doubt that will happen. My question is this: should I bother taking the covers off, or should I just leave them until all chance of frost has passed, tomorrow morning? Obviously I'll take the plastic bottles off if the sun comes out, but I was wondering if it's all right to leave the coverings on. Thanks in advance for any help! I'm a really n00b gardener, so if this question is silly, I apologize.
How’d he get aaalll the way over there?

How’d he get aaalll the way over there?

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