I don’t quite follow what you’re meaning by changing the card after you grade it for the second time, but as for sentence cards lots of people do them. The most important thing for using an srs is to just pick a format that works for you and stick with it—a difference in acquisition speed might exist between sentence and vocab cards (we have no data one way or the other on this), but realistically all of your acquisition will occur during immersion so it doesn’t matter much. Personally, the purpose of jp1k is to learn the meaning of words and not worry about reading until later. Using a sentence card might make that a little awkward if you don’t know how to read parts of the sentence or aren’t familiar with the grammar used. Additionally, it’ll add to the time you’re spending with the srs a little bit. It’s up to you, I’ll let others chime in with their opinions as well instead of making any definitive recommendations.