In the last month alone, Ford has developed a range of new cars...
Could be rephrased as:
Since last month (alone), Ford has developed a range of new cars...
??

Too weird for my liking!!
Anyway, you´ve just showed me a real gem here
http://www.englishpage.com/verbpage/presentperfect.html

I´ve never heard of such combination:
Have you been to Mexico in the last year.
I have seen that movie six times in the last month.
They have had three tests in the last week.

I know that PPerfect goes along with: since, so far, from that point on...but in the last month??

You live and learn!! Is there any other "pegadinha" around???