The interviewer made everything sound wonderful (just like their recruitment website). Once they finished and you had no questions, you were asked to sign a contract (but the contract seemed somewhat strange). Simply put, if you can’t accept split shifts, there’s no need to apply to this company.
Even part-time work is the same as full-time: all shifts are split shifts, with no choice. If you take the job, you have to work the entire day, and the hourly rate is not worthwhile when calculated out. There is no complete SOP for training new employees, and each senior employee may explain things differently. During a single day’s shift, you might hear two or more different ways of doing things, so you have to use different methods depending on which senior employee you’re working with.