<human>: Can you provide a brief overview of the text?

So, I am leaving a 3rd shift position to work first shift at another company. Right now we have 4 total workers (we're histotechs-not imperative for advice) 3 on third, and one on first shift. One of my coworkers put in her two weeks already & today I was offered a job. The two remaining coworkers have week long vacations scheduled (separate weeks) ending around July 11th. For some reason while being offered the job my ignoramus of a gut told this woman what was going on & that if I left any earlier my work would be left with a staff of ONE to do 4 peoples jobs. My coworker has explicitly stated she will not come in on days she asked off for a year ago. The HR lady told me she would try to work it out & I told her if it is a dealbreaker I will FOR SURE start earlier but I had to ask out of respect for my 2 remaining coworkers. 
   My plan : call HR lady back tomorrow to try & confirm July 11th start date. Give my work notice 3 weeks out (I will be treated like an asshole for my remaining time there, no point in giving notice sooner). Also, staying in contact with new company often.
<bot>: Trying not to screw over my coworkers while quitting at the same time some else is quitting but awkwardly told new job that I couldn't start for a month. Shit