correct, its ability shifts at the start of every turn, (or I guess the end if this is impossible)
So, for one turn, you can use the ability on the weapon.
More than anythnig this would work in a rainbow or flying deck, combine the two and you end up with a flying deck with the potential to have access to several forms of CC in the same turn, or for example with Fahrenheit you would get one turn of the fiery effect.