Landis Communications interview questions

I had applied multiple times to work at Landis Communications. Originally I had applied to be an intern while I was still in college and then again once I graduated. On both occasions, it took a very long time to hear back from them even when I emailed team members directly who I had previously networked with. I finally heard back via email for a phone interview. This interview went well and so I was asked to come in for an in-person meeting with a few team members and David Landis himself. At the same interview, I was asked to do a 30 min timed writing prompt. Everything seemed to go well as I was called almost immediately after my interview to be offered the position. As I was interviewing with a few companies at the time I asked to have two days to review the offer and get back to them to which they said yes and gave me till the end of the week at noon to get back to them. Only a day later after my offer did they send me an email that they rescinded my offer for no reason at all. I replied to this email creating a paper trail asking why they offered me the job gave me the salary they would give me and benefits package just to take it back the following day. The response was even more bizarre as they then told me it was because someone else could start sooner...this was so odd given that in my interview I let them know I could start right away (that coming Monday) and that I had been out of a job for almost two months so I wanted to start as soon as possible. All in all, make sure that if you are offered a job from this company that they send you a written letter and not just a verbal one so that they cannot so easily rescind your offer. I held this company in high regard for how small of a team they have but this is a terrible business practice and unethical.